Dimensionally stable silicone hydrogel contact lenses

ABSTRACT

Dimensionally stable silicone hydrogel contact lenses are described. The lenses are derived from a polymerizable composition including a first siloxane monomer represented by formula (1): 
     
       
         
         
             
             
         
       
         
         
           
             wherein m of formula (1) represents one integer from 3 to 10, n of formula (1) represents one integer from 1 to 10, R 1  of formula (1) is an alkyl group having from 1 to 4 carbon atoms, and each R 2  of formula (1) is independently either a hydrogen atom or a methyl group; the lenses also include units derived from a second siloxane monomer represented by formula (2): 
           
         
       
    
     
       
         
         
             
             
         
       
         
         
           
             wherein R 1  of formula (2) is selected from either hydrogen atom or a methyl group; R 2  of formula (2) is selected from either of hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2) represents an integer of from 0 to 10; n of formula (2) represents an integer of from 4 to 100; a and b represent integers of 1 or more; a+b is equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration of siloxane units includes a random configuration, the second siloxane monomer having a number average molecular weight of at least 3,000 daltons that is present in the polymerizable composition in an amount such that ratio of the first siloxane monomer to the second siloxane monomer is at least 2:1 based on unit parts by weight. Batches of silicone hydrogel contact lenses and methods of making silicone hydrogel contact lenses are also described.

This application claims the benefit under 35 U.S.C. §119(e) of priorU.S. Provisional Patent Application No. 61/447,164, filed Feb. 28, 2011,which is incorporated in its entirety by reference herein.

FIELD

The present disclosure is directed to silicone hydrogel contact lensesand related compositions and methods.

BACKGROUND

Commercially and clinically, silicone hydrogel contact lenses are apopular alternative to conventional hydrogel contact lenses (i.e.,hydrogel contact lenses that do not contain silicone orsilicone-containing ingredients). The presence of siloxanes in siliconehydrogel contact lens formulations is believed to affect the propertiesof silicone hydrogel contact lenses obtained therefrom. For example, itis believed that the presence of a siloxane component in a contact lensresults in a relatively higher oxygen permeability compared to aconventional hydrogel contact lens without a siloxane component. Inaddition, it is believed that the presence of a silicone componentincreases the likelihood of hydrophobic domains being present on thelens surface of a silicone hydrogel contact lens as compared to aconventional hydrogel contact lens without a silicone component.Techniques have been developed to overcome the hydrophobicity issues ofsilicone hydrogel contact lens surfaces. Based on the popularity ofsilicone hydrogel contact lenses, there continues to be a need for newsilicone hydrogel contact lenses that are ophthalmically compatible.

Some documents describing silicone hydrogel contact lenses include: U.S.Pat. No. 4,711,943, U.S. Pat. No. 5,712,327, U.S. Pat. No. 5,760,100,U.S. Pat. No. 7,825,170, U.S. Pat. No. 6,867,245, US20060063852,US20070296914, U.S. Pat. No. 7,572,841, US20090299022, US20090234089,and US20100249356, each of which is incorporated in its entirety byreference herein.

SUMMARY

It has been discovered that many silicone hydrogel contact lenses madeduring a contact lens development process can have stability issues,such as undesired changes in physical dimensions of the siliconehydrogel contact lenses over time. Such stability issues can impact theshelf-life of the silicone hydrogel contact lenses and compromise themanufacture of silicone hydrogel contact lenses on a commercial scale.The reduced stability of silicone hydrogel contact lenses, compared toconventional hydrogel contact lenses, may be attributed, at least inpart, to hydrolytic decomposition or degradation of the siloxanespresent in the formulations used to produce the contact lenses, or thesiloxanes present in the polymerized contact lenses. From amanufacturing perspective, it is important for silicone hydrogel contactlenses to remain dimensionally stable over long periods of time so thatthe physical dimensions of the contact lenses remain within targetspecifications approved by regulatory agencies over the shelf life ofthe product.

As an example, it has now been discovered that silicone hydrogel contactlenses made from polymerizable compositions containing a single siloxanerepresented by formula (1):

wherein m of formula (1) is 4, n of formula (1) is 1, and R¹ of formula(1) is a butyl group, and each R² of formula (1) is independently eithera hydrogen atom or a methyl group; along with other non-silicon reactivemonomers, are not dimensionally stable over long periods of time. Forexample, such silicone hydrogel contact lenses appeared to have a shelflife of less than about 2 years based on average changes in contact lensdiameter during accelerated shelf life studies conducted at elevatedtemperatures (i.e., at temperatures above room temperature). Thisdimensional instability observed in contact lenses made fromformulations containing only this siloxane of formula (1) was observedeven when a cross-linking agent was present in the formulation.

Based on this discovery, new silicone hydrogel contact lenses have beeninvented. Unlike approaches which improved dimensional stability of asilicone hydrogel contact lens by manipulating the contact lenspackaging solution ingredients or pH, the present disclosure is relatedto the discovery that including a second siloxane represented by formula(2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltonscan improve the dimensional stability of the silicone hydrogel contactlenses that are made from formulations containing the siloxane offormula (1), and thus result in silicone hydrogel contact lenses thathave a commercially acceptable shelf life.

The present disclosure relates to new silicone hydrogel contact lenses.A silicone hydrogel contact lens, in accordance with the presentdisclosure, comprises a polymeric lens body. The polymeric lens body isthe reaction product of a polymerizable composition. The polymerizablecomposition comprises a plurality of lens forming ingredients, such thatwhen the composition is polymerized, a polymeric lens body is obtained.

In one example, the present disclosure is directed to a polymerizablecomposition used to produce the present silicone hydrogel contactlenses. The polymerizable composition comprises a first siloxane monomerrepresented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomer. Thesecond siloxane monomer has a structure represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has number average molecular weight of at least 3,000 daltons.In this example, the first siloxane monomer and the second siloxanemonomer can be present in amounts effective to provide a dimensionallystable silicone hydrogel contact lens. For example, the first siloxanemonomer and the second siloxane monomer can be present in thepolymerizable composition in a ratio of at least 2:1 based on unit partsby weight of the first siloxane monomer to the second siloxane monomer.Optionally in this example, the first siloxane monomer can have a numberaverage molecular weight from 400 daltons to 700 daltons, or the secondsiloxane monomer can have a number average molecular weight greater than7,000 daltons, or both. In addition to the two siloxane monomers, thepolymerizable composition also comprises at least one hydrophilicmonomer, or at least one hydrophobic monomer, or at least onecross-linking agent, or any combination thereof. Optionally in thisexample, when the polymerizable composition comprises the at least onehydrophilic monomer, the at least one hydrophilic monomer can be presentin the polymerizable composition in an amount from 30 unit parts to 60unit parts, or the at least one hydrophilic monomer can comprise atleast one hydrophilic vinyl-containing monomer, such as, for example, atleast one hydrophilic amide-containing monomer having one N-vinyl group,or both. Also optionally in this example, when the polymerizablecomposition comprises the at least one cross-linking agent, the at leastone cross-linking agent can comprise a vinyl-containing cross-linkingagent.

In another example, the present disclosure is also directed to asilicone hydrogel contact lens which comprises a polymeric lens bodythat is the reaction product of a polymerizable composition. Thepolymerizable composition comprises a first siloxane monomer representedby formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The ingredients of the polymerizable composition can be present in thepolymerizable composition in amounts such that the fully hydratedsilicone hydrogel contact lens has an oxygen permeability of at least 55barrers, or an equilibrium water content from about 30% to about 70% byweight, or a tensile modulus from about 0.2 MPa to about 0.9 MPa, or anycombination thereof. In this silicone hydrogel contact lens, the firstsiloxane monomer and the second siloxane monomer are present in thepolymerizable composition in a ratio of at least 2:1 based on unit partsby weight of the first siloxane monomer to the second siloxane monomer.

Optionally in this example, the first siloxane monomer can have a numberaverage molecular weight from 400 daltons to 700 daltons, or the secondsiloxane monomer can have a number average molecular weight greater than7,000 daltons, or both. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. Alsooptionally in this example, when the polymerizable composition comprisesthe at least one hydrophilic monomer, the at least one hydrophilicmonomer can be present in the polymerizable composition in an amountfrom 30 unit parts to 60 unit parts, or the at least one hydrophilicmonomer can comprise at least one hydrophilic vinyl-containing monomer,such as, for example, at least one hydrophilic amide-containing monomerhaving one N-vinyl group, or both. Also optionally in this example, whenthe polymerizable composition comprises the at least one cross-linkingagent, the at least one cross-linking agent can comprise avinyl-containing cross-linking agent. In one particular lens of thisexample, the silicone hydrogel contact lens has an oxygen permeabilityof at least 55 barrers, an equilibrium water content from about 35% toabout 65% by weight, and a tensile modulus from about 0.2 MPa to about0.9 MPa.

The present disclosure is also directed to a batch of silicone hydrogelcontact lenses comprising a plurality of contact lenses formed frompolymeric lens bodies which are the reaction product of thepolymerizable composition described herein. The batch of siliconehydrogel contact lenses comprise the polymerizable composition describedabove, or comprise a plurality of silicone hydrogel contact lensesdescribed above, or both, and have an average dimensional stabilityvariance of less than plus or minus three percent (±3.0%), where theaverage dimensional stability variance is the variance in a value of aphysical dimension when measured at an initial time point within one dayof a manufacturing date of the batch of lenses, and at a second timepoint, where the second time point is from two weeks to seven yearsafter the initial time point when the batch is stored at roomtemperature, or, when the batch is stored at a higher temperature (i.e.,under accelerated shelf life testing conditions), the second time pointis a time point representative of storage of the batch from two weeks toseven years at room temperature, said average dimensional stabilityvariance being an average of the dimensional stability variancedetermined for at least 20 individual lenses of the batch by thefollowing equation (A):(Diameter_(Final)−Diameter_(Original)/Diameter_(Original))×100  (A).In one example, accelerated shelf life testing conditions which areespecially useful in determining average dimensional stability varianceare for 4 weeks at 70 degrees C., although other periods of time andtemperature can be used.

The present disclosure is also directed to methods of manufacturing asilicone hydrogel contact lens. The method of manufacturing comprisesthe steps of providing a polymerizable composition comprising a firstsiloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.Optionally in this example, the number average molecular weights of thefirst siloxane monomer, the second siloxane monomer, or both, can be asdescribed above. The polymerizable composition also comprises at leastone hydrophilic monomer, or at least one hydrophobic monomer, or atleast one cross-linking agent, or any combination thereof. Alsooptionally in this example, the components of the polymerizablecomposition can be as described above.

In any of the foregoing examples of polymerizable compositions, or ofpolymeric lens bodies, or of silicone hydrogel contact lenses, or ofbatches of silicone hydrogel contact lenses, or of methods ofmanufacturing contact lenses described above, the first siloxane monomercan be represented by formula (1) where m of formula (1) is 4, n offormula (1) is 1, R¹ of formula (1) is a butyl group, and each R² offormula (1) is independently either a hydrogen atom or a methyl group.Examples of the second siloxane are described below; or the secondsiloxane monomer can be represented by formula (2) wherein in the secondsiloxane monomer, m of formula (2) is 0, n of formula (2) is one integerfrom 5 to 10, a is one integer from 65 to 90, b is one integer from 1 to10, and R₁ of formula (2) is a methyl group; or both.

Additional embodiments of the polymerizable compositions, polymeric lensbodies, present lenses, lens products, batches of lenses, and methods ofmanufacturing contact lenses will be apparent from the followingdescription, Examples C1 and 1-25, and claims. As can be appreciatedfrom the foregoing and following description, each and every featuredescribed herein, and each and every combination of two or more of suchfeatures, and each and every combination of one or more values defininga range, are included within the scope of the present invention providedthat the features included in such a combination are not mutuallyinconsistent. In addition, any feature or combination of features or anyvalue(s) defining a range may be specifically excluded from anyembodiment of the present invention.

DETAILED DESCRIPTION

As described herein, it has now been discovered that silicone hydrogelcontact lenses that are formed from a polymerizable compositioncontaining only a single siloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group, are notdimensionally stable, even when a cross-linking agent is present in thepolymerizable composition. It has further been discovered that byincluding a second siloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanehas a number average molecular weight of at least 3,000 daltons, and byproviding the first siloxane monomer and the second siloxane monomer inthe polymerizable composition in a ratio of at least 2:1 based on unitparts by weight, silicone hydrogel contact lenses that are dimensionallystable can be produced.

As previously described, in the polymerizable compositions of thepresent disclosure, the first siloxane monomer and the second siloxanemonomer are present in the polymerizable composition in a ratio of atleast 2:1 based on unit parts by weight. In other words, for every unitpart by weight of the second siloxane monomer present in thepolymerizable composition, 2 or more unit parts of the first siloxanemonomer are also present in the polymerizable composition. In accordancewith the present disclosure, the first siloxane monomer and the secondsiloxane monomer can be present in the polymerizable composition in aratio from about 2:1 to about 10:1 based on unit parts by weight of thefirst siloxane monomer to the second siloxane monomer. In anotherexample, the first siloxane monomer and the second siloxane monomer canbe present in the polymerizable composition in a ratio from about 3:1 toabout 6:1 based on unit parts by weight. In yet another example, thefirst siloxane monomer and the second siloxane monomer can be present inthe polymerizable composition in a ratio of about 4:1 based on unitparts by weight.

As used herein, ‘unit parts’ is understood to mean unit parts by weight.For example, to prepare a formulation described as comprising z unitparts of a siloxane monomer and y unit parts of a hydrophilic monomer,the composition can be prepared by combining z grams of the siloxanemonomer with y grams of the hydrophilic monomer to obtain a total of y+zgrams of polymerizable composition, or by combining z ounces of thesiloxane with y ounces of the hydrophilic monomer to obtain a total ofy+z ounces of polymerizable composition, and so on. When the compositionfurther comprises additional optional ingredients such as, for example,x unit parts of a cross-linking agent, x grams of the cross-linkingagent are combined with z grams of the siloxane monomer and y grams ofthe hydrophilic monomer to obtain a total of x+y+z grams ofpolymerizable composition, and so on. When the composition comprises anadditional optional ingredient comprising an ingredient componentcomposed of two ingredients, such as, for example, a hydrophobic monomercomponent consisting of a first hydrophobic monomer and a secondhydrophobic monomer, in addition to the z unit parts of siloxanemonomer, the y unit parts of hydrophilic monomer and the x unit parts ofthe cross-linker, w unit parts of the first hydrophobic monomer and vunit parts of the second hydrophobic monomer are combined to obtain atotal amount of v+w+x+y+z unit parts of the polymerizable composition.It is understood that the unit parts of the at least one hydrophobicmonomer present in such a polymerizable is the sum of the unit parts ofthe first hydrophobic monomer and the unit parts of the secondhydrophobic monomer, e.g., v+w unit parts in this example. Typically, aformula for a polymerizable composition will be composed of ingredientsin amounts totaling from about 90 to about 110 unit parts by weight.When amounts of components of the polymerizable composition are recitedherein as being in unit parts, it is to be understood that the unitparts of these component are based on a formula providing a total weightof the composition ranging from about 90 to 110 unit parts. In oneexample, the unit parts by weight can be based on a formula providing atotal weight of the composition ranging from about 95 to 105 unit partsby weight, or from about 98 to 102 unit parts by weight.

The present contact lenses comprise, or consist of, hydrated lens bodiescomprising a polymeric component and a liquid component. The polymericcomponent comprises units of two or more siloxane monomers (i.e., asiloxane monomer of formula (1), a second siloxane monomer of formula(2), and optionally one or more additional siloxane monomers), and oneor more non-silicon polymerizable ingredients (i.e., one or morehydrophilic monomers, one or more hydrophobic monomers, one or morecross-linking agents, or any combination thereof). It can therefore beunderstood that the polymeric component is the reaction product of apolymerizable composition comprising two or more siloxane monomers (twoor more siloxane monomers present as the siloxane monomer component ofthe composition), and one or more non-silicon reactive ingredients. Asused herein, a non-silicon reactive ingredient is understood to be aningredient which has a polymerizable double bond as part of itsmolecular structure, but which does not have a silicon atom in itsmolecular structure. The ingredients of the polymerizable compositioncan be monomers, macromers, pre-polymers, polymers, or any combinationthereof. In addition to the first siloxane monomer of formula (1), thepolymerizable composition further includes a second siloxane monomer, orat least one cross-linking agent, or both a second siloxane monomer andat least one cross-linking agent. The at least one cross-linking agent,the at least one hydrophilic monomer, and the at least one hydrophobicmonomer of the polymerizable composition are understood to benon-silicon polymerizable ingredients. As used herein, the at least onecross-linking agent can be understood to comprise a single cross-linkingagent, or to comprise a cross-linking agent component composed of two ormore cross-linking agents. Similarly, the at least one hydrophilicmonomer can be understood to comprise a single hydrophilic monomer, orto comprise a hydrophilic monomer component composed of two or morehydrophilic monomers. The at least one hydrophobic monomer can beunderstood to comprise a single hydrophobic monomer, or to comprise ahydrophobic monomer component composed of two or more hydrophobicmonomers. The optional at least one third siloxane monomer can beunderstood to comprise a single third siloxane monomer, or to comprise athird siloxane monomer component composed of two or more siloxanemonomers. Additionally, the polymerizable composition can optionallyinclude at least one initiator, or at least one organic diluent, or atleast one surfactant, or at least one oxygen scavenger, or at least onetinting agent, or at least one UV absorber, or at least one chaintransfer agent, or any combination thereof. The optional at least oneinitiator, at least one organic diluent, at least one surfactant, atleast one oxygen scavenger, at least one tinting agent, at least one UVabsorber, or at least one chain transfer agent are understood to benon-silicon ingredients, and can be either non-polymerizable ingredientsor polymerizable ingredients (i.e., ingredients having a polymerizablefunctional group as part of their molecular structure).

The combination of the polymeric component and the liquid component arepresent as a hydrated lens body, which is suitable for placement on aneye of a person. The hydrated lens body has a generally convex anteriorsurface and a generally concave posterior surface, and has anequilibrium water content (EWC) greater than 10% weight by weight(wt/wt). Thus, the present contact lenses can be understood to be softcontact lenses, which as used herein, refers to contact lenses that,when fully hydrated, can be folded upon themselves without breaking.

As understood in the industry, a daily disposable contact lens is anunworn contact lens that is removed from its sealed, sterilized package(primary package) produced by a contact lens manufacturer, placed on aperson's eye, and is removed and discarded after the person is donewearing the lens at the end of the day. Typically, the duration of lenswear for daily disposable contact lenses is from eight to fourteenhours, and they are then disposed of after wear. Daily disposable lensesare not cleaned or exposed to cleaning solutions prior to placement inthe eye since they are sterile prior to opening the package. A dailydisposable silicone hydrogel contact lens is a disposable siliconehydrogel contact lens that is replaced daily. In contrast, non-dailydisposable contact lenses are disposable contact lenses that arereplaced less frequently than daily (e.g., weekly, bi-weekly, ormonthly). Non-daily disposable contact lenses are either removed fromthe eye and cleaned with a cleaning solution on a regular basis, or areworn continuously without removal from the eye. The present contactlenses can be either daily disposable contact lenses or non-dailydisposable contact lenses.

In one example, the polymerizable composition of the present disclosurecomprises a first siloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. In otherwords, on a single molecule of the siloxane monomer represented byformula 1, the first R² of formula (1), (the R² which is closest to theR¹ end group on the left side of the molecule), can be either a hydrogenatom or a methyl group, and the second R² of formula (1) (the R² whichis part of the methacrylate end group on the right side of themolecule), can also be either a hydrogen atom or a methyl group,regardless of whether the first R² of formula (1) is a hydrogen atom ora methyl group. The polymerizable composition also comprises a secondsiloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof.

The present disclosure also relates to a new silicone hydrogel contactlens or to new silicone hydrogel contact lenses. A silicone hydrogelcontact lens in accordance with the present disclosure comprises apolymeric lens body. The polymeric lens body is the reaction product ofa polymerizable composition or contact lens formulation. Thepolymerizable composition used to produce the present silicone hydrogelcontact lens or lenses comprises a first siloxane monomer represented byformula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof.

As used herein, a molecular weight is understood to refer to the numberaverage molecular weight. The number average molecular weight is theordinary arithmetic mean or average of the molecular weights of theindividual molecules present in the sample of a monomer. As theindividual molecules in a sample of monomer may vary slightly from oneanother in molar mass, some level of polydispersity may be present inthe sample. As used herein, when the second siloxane monomer, or anyother monomer, macromer, pre-polymer, or polymer, of the polymerizablecomposition is polydisperse, the term “molecular weight” refers to thenumber average molecular weight of the monomer or ingredient. As oneexample, a sample of the second siloxane monomer can have a numberaverage molecular weight of about 15,000 daltons, but if the sample ispolydisperse, the actual molecular weights of the individual monomerspresent in the sample may range from 12,000 daltons to 18,000 daltons.

The number average molecular weight can be the absolute number averagemolecular weight as determined by proton nuclear magnetic resonance(NMR) end group analysis, as understood by persons of ordinary skill inthe art. Molecular weights may also be determined using gel permeationchromatography, as understood by persons of ordinary skill in the art,or may be provided by suppliers of the chemicals.

The molecular weight of the first siloxane monomer is less than 2,000daltons. In one example, the molecular weight of the first siloxanemonomer can be less than 1,000 daltons. In another example, themolecular weight of the first siloxane monomer can be from 400 to 700daltons. Additional details of the first siloxane monomer can beunderstood from US20090299022, the entire content of which is herebyincorporated by reference. As can be appreciated from formula (1), thefirst siloxane monomer has a single methacrylate polymerizablefunctional group present on one end of the main chain of the siloxanemonomer.

An example of a polymerizable composition in accordance with the presentdisclosure comprises a first siloxane monomer represented by formula(1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group, wherein thefirst siloxane monomer has a number average molecular weight of from 400daltons to 700 daltons. The polymerizable composition of this examplealso comprises a second siloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. Optionallyin this example, the at least one hydrophilic monomer can comprise ahydrophilic vinyl-containing monomer, including a hydrophilicamide-containing monomer having one N-vinyl group; or can comprise avinyl-containing cross-linking agent, or both.

In one example of the present contact lenses, the second siloxanemonomer can have a number average molecular weight of at least 4,000daltons, or at least 7,000 daltons, or at least 9,000 daltons, or atleast 11,000 daltons. The number average molecular weight of the secondsiloxane monomer can be less than 20,000 daltons. Thus, in somecontexts, the second siloxane monomer can be considered a macromer, butit will be referred to as a monomer herein since it forms a unit part ofa polymer formed with the other reactive components of the polymerizablecomposition.

Another example of a polymerizable composition in accordance with thepresent disclosure comprises a first siloxane monomer represented byformula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition of this example also comprises a secondsiloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 7,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. Optionallyin this example, the at least one hydrophilic monomer can comprise ahydrophilic vinyl-containing monomer, including a hydrophilicamide-containing monomer having one N-vinyl group; or can comprise avinyl-containing cross-linking agent, or both.

Yet another example of a polymerizable composition in accordance withthe present disclosure comprises a first siloxane monomer represented byformula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group, wherein thefirst siloxane monomer has a number average molecular weight of from 400daltons to 700 daltons. The polymerizable composition of this examplealso comprises a second siloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 7,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. Optionallyin this example, the at least one hydrophilic monomer can comprise ahydrophilic vinyl-containing monomer, including a hydrophilicamide-containing monomer having one N-vinyl group; or can comprise avinyl-containing cross-linking agent, or both.

As previously stated, the polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. As usedherein, the preceding three types of chemicals are non-silicon chemicals(i.e., chemicals whose molecular structure does not include a siliconatom) and thus are different from the siloxane monomers present in thepolymerizable compositions. The polymerizable compositions can beunderstood to comprise at least two siloxane monomers, and othernon-silicon hydrophilic monomers, or non-silicon hydrophobic monomers,or non-silicon cross-linking agents, or any combination thereof,although, optionally, the polymerizable composition can further compriseat least a third siloxane monomer.

The first siloxane monomer, the second siloxane monomer and the optionalat least one third siloxane monomer comprise the siloxane monomercomponent of the polymerizable composition. Each of the first siloxanemonomer, or the second siloxane monomer, or the optional third siloxanemonomer, or any combination thereof, can be a hydrophilic siloxanemonomer, or a hydrophobic siloxane monomer, or can have both hydrophilicregions and hydrophobic regions, depending on the amount and location ofany hydrophilic components, such as units of ethylene glycol,polyethylene glycol and the like, present in the molecular structure ofthe siloxane monomers. For example, the second siloxane monomer, or theoptional at least one third siloxane monomer, or any combinationthereof, can contain hydrophilic components within the main chain of thesiloxane molecule, can contain hydrophilic components within one or moreside chains of the siloxane molecule, or any combination thereof. Forexample, the siloxane monomer can have at least one unit of ethyleneglycol adjacent to a polymerizable functional group in the main chain ofthe siloxane molecule. As used herein, adjacent is understood to meanboth immediately adjacent, and separated only by 10 or fewer carbonatoms The at least one unit of ethylene glycol adjacent to apolymerizable functional group in the main chain of the siloxanemolecule can be separated from the polymerizable functional group by acarbon chain 1-5 units in length (i.e., where the ethylene glycol unitis bonded to the first carbon in the carbon chain 1-5 units in length,and the polymerizable functional group is bonded to the last carbon ofthe carbon chain 1-5 units in length, in other words, the ethyleneglycol unit and the polymerizable group are not immediately adjacent butare separated by 1-5 carbon atoms). The siloxane monomer can have atleast one unit of ethylene glycol adjacent to polymerizable functionalgroups present on both ends of the main chain of the siloxane molecule.The siloxane monomer can have at least one unit of ethylene glycolpresent in at least one side chain of the siloxane molecule. The atleast one unit of ethylene glycol present in at least one side chain ofthe siloxane molecule can be part of a side chain bonded to a siliconatom of the main chain of the siloxane molecule. The siloxane moleculecan have both at least one unit of ethylene glycol adjacent topolymerizable functional groups present on both ends of the main chainof the siloxane molecule, and at least one unit of ethylene glycolpresent in at least one side chain of the siloxane molecule.

The hydrophilicity or hydrophobicity of a monomer can be determinedusing conventional techniques, such as, for example, based on themonomer's aqueous solubility. For purposes of the present disclosure, ahydrophilic monomer is a monomer that is visibly soluble in an aqueoussolution at room temperature (e.g. about 20-25 degrees C.). For example,a hydrophilic monomer can be understood to be any monomer for which 50grams or more of the monomer are visibly fully soluble in 1 liter ofwater at 20 degrees C. (i.e., the monomer is soluble at a level of atleast 5% wt/wt in water) as determined using a standard shake flaskmethod as known to persons of ordinary skill in the art. A hydrophobicmonomer, as used herein, is a monomer that is visibly insoluble in anaqueous solution at room temperature, such that separate, visuallyidentifiable phases are present in the aqueous solution, or such thatthe aqueous solution appears cloudy and separates into two distinctphases over time after sitting at room temperature. For example, ahydrophobic monomer can be understood to be any monomer for which 50grams of the monomer are not visibly fully soluble in 1 liter of waterat 20 degrees C. (i.e., the monomer is soluble at a level of less than5% wt/wt in water).

In one example of the present contact lenses, the first siloxane monomercan be represented by formula (1) where m of formula (1) is 4, n offormula (1) is 1, R¹ of formula (1) is a butyl group, and each R² offormula (1) is independently either a hydrogen atom or a methyl group.One example of such a first siloxane monomer is identified herein as Si1in Examples C1 and 1-25. An example of a polymerizable composition usedto produce the present silicone hydrogel contact lens or lensescomprises a first siloxane monomer represented by formula (1):

wherein m of formula (1) is 4, n of formula (1) is 1, R¹ of formula (1)is a butyl group, and each R² of formula (1) is independently either ahydrogen atom or a methyl group. The polymerizable composition of thisexample also comprises a second siloxane monomer represented by formula(2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. Optionallyin this example, the at least one hydrophilic monomer can comprise ahydrophilic vinyl-containing monomer, including a hydrophilicamide-containing monomer having one N-vinyl group; or can comprise avinyl-containing cross-linking agent, or both.

Another example of a polymerizable composition used to produce thepresent silicone hydrogel contact lens or lenses comprises a firstsiloxane monomer represented by formula (1):

wherein m of formula (1) is 4, n of formula (1) is 1, R¹ of formula (1)is a butyl group, and each R² of formula (1) is independently either ahydrogen atom or a methyl group, wherein the first siloxane monomer hasa number average molecular weight of from 400 daltons to 700 daltons.The polymerizable composition of this example also comprises a secondsiloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. Optionallyin this example, the at least one hydrophilic monomer can comprise ahydrophilic vinyl-containing monomer, including a hydrophilicamide-containing monomer having one N-vinyl group; or can comprise avinyl-containing cross-linking agent, or both.

Yet another example of a polymerizable composition used to produce thepresent silicone hydrogel contact lens or lenses comprises a firstsiloxane monomer represented by formula (1):

wherein m of formula (1) is 4, n of formula (1) is 1, R¹ of formula (1)is a butyl group, and each R² of formula (1) is independently either ahydrogen atom or a methyl group. The polymerizable composition of thisexample also comprises a second siloxane monomer represented by formula(2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 7,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof. Optionallyin this example, the at least one hydrophilic monomer can comprise ahydrophilic vinyl-containing monomer, including a hydrophilicamide-containing monomer having one N-vinyl group; or can comprise avinyl-containing cross-linking agent, or both.

As previously stated, in the present silicone hydrogel contact lenses,the second siloxane monomer is represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; and the configurationof siloxane units includes a random configuration. In one example inwhich the second siloxane monomer is a monomer represented by formula(2), m of formula (2) is 0, n of formula (2) is an integer from 5 to 15,a is an integer from 65 to 90, b is an integer from 1 to 10, R₁ offormula (2) is a methyl group, and R₂ of formula (2) is either ahydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms. Oneexample of such a second siloxane monomer as represented by formula (2)is abbreviated Si2 in Examples C1 and 1-25. The number average molecularweight for this second siloxane monomer represented by formula (2) canbe from about 9,000 daltons to about 10,000 daltons. In another example,the second siloxane monomer represented by formula (2) can have amolecular weight from about 5,000 daltons to about 10,000 daltons. Itcan be appreciated that the second siloxane represented by formula (2)is a bifunctional siloxane having two terminal methacrylatepolymerizable functional groups (i.e., a methacrylate group present oneach end of the main siloxane chain of the molecule). Additional detailsof this second siloxane monomer can be found in US20090234089, theentire content of which is incorporated herein by reference.

An example of a polymerizable composition used to produce the presentsilicone hydrogel contact lens or lenses comprises a first siloxanemonomer represented by formula (1):

where m of formula (1) represents one integer from 3 to 10, n of formula(1) represents one integer from 1 to 10, R¹ of formula (1) is an alkylgroup having from 1 to 4 carbon atoms, and each R² of formula (1) isindependently either a hydrogen atom or a methyl group. Thepolymerizable composition of this example also comprises a secondsiloxane monomer represented by formula (2):

wherein m of formula (2) is 0, n of formula (2) is an integer from 5 to15, a is an integer from 65 to 90, b is an integer from 1 to 10, R₁ offormula (2) is a methyl group, and R₂ of formula (2) is either ahydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms and thesecond siloxane has a number average molecular weight of at least 7,000daltons. The first siloxane monomer and the second siloxane monomer arepresent in the polymerizable composition in a ratio of at least 2:1based on unit parts by weight. The polymerizable composition alsocomprises at least one hydrophilic monomer, or at least one hydrophobicmonomer, or at least one cross-linking agent, or any combinationthereof. Optionally in this example, the at least one hydrophilicmonomer can comprise a hydrophilic vinyl-containing monomer, including ahydrophilic amide-containing monomer having one N-vinyl group; or cancomprise a vinyl-containing cross-linking agent, or both.

Another example of a polymerizable composition used to produce thepresent silicone hydrogel contact lens or lenses comprises a firstsiloxane monomer represented by formula (1):

wherein m of formula (1) is 4, n of formula (1) is 1, R¹ of formula (1)is a butyl group, and each R² of formula (1) is independently either ahydrogen atom or a methyl group, and the first siloxane monomer has anumber average molecular weight of from 400 daltons to 700 daltons. Thepolymerizable composition of this example also comprises a secondsiloxane monomer represented by formula (2):

wherein m of formula (2) is 0, n of formula (2) is an integer from 5 to15, a is an integer from 65 to 90, b is an integer from 1 to 10, R₁ offormula (2) is a methyl group, and R₂ of formula (2) is either ahydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms and thesecond siloxane has a number average molecular weight of at least 7,000daltons. The first siloxane monomer and the second siloxane monomer arepresent in the polymerizable composition in a ratio of at least 2:1based on unit parts by weight. The polymerizable composition alsocomprises at least one hydrophilic monomer, or at least one hydrophobicmonomer, or at least one cross-linking agent, or any combinationthereof. Optionally in this example, the at least one hydrophilicmonomer can comprise a hydrophilic vinyl-containing monomer, including ahydrophilic amide-containing monomer having one N-vinyl group; or cancomprise a vinyl-containing cross-linking agent, or both. Thepolymerizable compositions used to prepare the present silicone hydrogelcontact lenses can also include optional additional ingredients otherthan those described above. For example, a polymerizable composition caninclude at least one third siloxane monomer. As another example of abifunctional siloxane monomer useful in the present silicone hydrogelcontact lenses, the optional third (or more) siloxane monomer can berepresented by formula (3):

wherein R³ is selected from either hydrogen atom or a methyl group, m offormula (3) represents an integer from 0 to 10, and n of formula (3)represents an integer from 1 to 500. In one example, the second siloxanemonomer is represented by formula 3, and R³ is a methyl group, m offormula (3) is 0, and n of formula (3) is one integer from 40 to 60. Thesecond siloxane monomer of this example is represented by formula (4),and is abbreviated Si3 in Examples C1 and 1-25 (available from Gelest,Inc. (Morrisville, Pa., USA) as product code DMS-R18):

The siloxane of formula (4) can have a number average molecular weightfrom about 4,000 to about 4,500 daltons.

The polymerizable compositions used to prepare the present siliconehydrogel contact lenses can also include optional additional ingredientsother than those described above. For example, as discussed above, apolymerizable composition can include at least one third siloxanemonomer. The polymerizable compositions can comprise one third siloxanemonomer, or can comprise a third siloxane monomer component where thethird siloxane monomer component is comprised of two or more onesiloxane monomers, each of which differ from the first siloxane monomerand the second siloxane monomer of the polymerizable composition.Examples of the third siloxane monomer or third siloxane monomercomponent can include poly (organosiloxane) monomers or macromers orprepolymers, such as, for example, 3-[tris(trimethylsiloxy)silyl]propylallyl carbamate, or 3-[tris(trimethylsiloxy)silyl]propyl vinylcarbamate, or trimethylsilylethyl vinyl carbonate, ortrimethylsilylmethyl vinyl carbonate, or 3-[tris(trimethylsilyloxy)silyl]propyl methacrylate (TRIS), or 3-methaycryloxy-2-hydroxypropyloxy)propylbis(trimethylsiloxy)methylsilane (SiGMA), or methyldi(trimethylsiloxy) silylpropylglycerolethyl methacrylate (SiGEMA), ormonomethacryloxypropyl terminated polydimethylsiloxane (MCS-M11),MCR-M07, or monomethacryloxypropyl terminated mono-n-butyl terminatedpolydimethyl siloxane (mPDMS), or any combination thereof. In oneexample of a polymerizable composition of the present disclosure, the atleast one third siloxane can comprise one or more of the first siloxanesdescribed herein or the second siloxanes described herein, wherein theat least one third siloxane differs from the first siloxane and thesecond siloxane present in the polymerizable composition based onmolecular weight, molecular formula, or both molecular weight andformula. For example, the third siloxane monomer can be a siloxanemonomer of formula (1) having a different molecular weight than thefirst siloxane monomer of the polymerizable composition. In anotherexample, the at least one third siloxane can comprise at least one ofthe siloxanes disclosed in the following patents: US2007/0066706,US2008/0048350, U.S. Pat. No. 3,808,178, U.S. Pat. No. 4,120,570, U.S.Pat. No. 4,136,250, U.S. Pat. No. 4,153,641, U.S. Pat. No. 470,533, U.S.Pat. No. 5,070,215, U.S. Pat. No. 5,998,498, U.S. Pat. No. 5,760,100,U.S. Pat. No. 6,367,929, and EP080539, the entire content of which arehereby incorporated by reference.

The total amount of siloxane monomers present in the polymerizablecomposition (e.g., the sum of the unit parts of the first siloxanemonomer, the second siloxane monomer, and any other optional siloxanemonomers present in the polymerizable composition) can be from about 10to about 60 unit parts, or from about 25 to about 50 unit parts, or fromabout 35 to about 40 unit parts.

As previously stated, optionally, the polymerizable compositions of thepresent disclosure can comprise at least one hydrophilic monomer. Thehydrophilic monomer is understood to be a non-silicone polymerizableingredient having only one polymerizable functional group present in itsmolecular structure. The polymerizable compositions can comprise asingle hydrophilic monomer, or can comprise two or more hydrophilicmonomers present as the hydrophilic monomer component. Non-siliconhydrophilic monomers which can be used as the hydrophilic monomer or thehydrophilic monomer component in the polymerizable compositionsdisclosed herein include, for example, acrylamide-containing monomers,or acrylate-containing monomers, or acrylic acid-containing monomers, ormethacrylate-containing monomers, or methacrylic acid-containingmonomers, or any combination thereof. In one example, the hydrophilicmonomer or monomer component can comprise or consist of amethacrylate-containing hydrophilic monomer. It is understood that thehydrophilic monomer or hydrophilic monomer component is a non-siliconmonomer. Examples of hydrophilic monomers which can be included in thepresent polymerizable compositions can include, for example,N,N-dimethylacrylamide (DMA), or 2-hydroxyethyl acrylate, or2-hydroxyethyl methacrylate (HEMA), or 2-hydroxypropyl methacrylate, or2-hydroxybutyl methacrylate (HOB), or 2-hydroxybutyl acrylate, or4-hydroxybutyl acrylate glycerol methacrylate, or 2-hydroxyethylmethacrylamide, or polyethyleneglycol monomethacrylate, or methacrylicacid, or acrylic acid, or any combination thereof.

In one example, the hydrophilic monomer or hydrophilic monomer componentcan comprise or consist of a vinyl-containing monomer. Examples ofhydrophilic vinyl-containing monomers which can be provided in thepolymerizable compositions include, without limitation, N-vinylformamide, or N-vinyl acetamide, or N-vinyl-N-ethyl acetamide, orN-vinyl isopropylamide, or N-vinyl-N-methyl acetamide (VMA), or N-vinylpyrrolidone (NVP), or N-vinyl caprolactam, or N-vinyl-N-ethyl formamide,or N-vinyl formamide, or N-2-hydroxyethyl vinyl carbamate, orN-carboxy-β-alanine N-vinyl ester, or 1,4-butanediol vinyl ether (BVE),or ethylene glycol vinyl ether (EGVE), or diethylene glycol vinyl ether(DEGVE), or any combination thereof.

In another example, the hydrophilic monomer or hydrophilic monomercomponent of the polymerizable composition can comprise or consist of ahydrophilic amide monomer. The hydrophilic amide monomer can be ahydrophilic amide monomer having one N-vinyl group, such as, forexample, N-vinyl formamide, or N-vinyl acetamide, or N-vinyl-N-ethylacetamide, or N-vinyl isopropylamide, or N-vinyl-N-methyl acetamide(VMA), or N-vinyl pyrrolidone (NVP), or N-vinyl caprolactam, or anycombination thereof. In one example, the hydrophilic monomer orhydrophilic monomer component comprises N-vinyl-N-methyl acetamide(VMA). For example, the hydrophilic monomer or monomer component cancomprise or consist of VMA. In one particular example, the hydrophilicmonomer can be VMA.

In one example, the polymerizable composition of the present disclosurecomprises a first siloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one hydrophilic vinyl-containing monomer. Optionally,the polymerizable composition of this example can comprise avinyl-containing cross-linking agent

In another example, the polymerizable composition of the presentdisclosure comprises a first siloxane monomer represented by formula(1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one hydrophilic amide-containing monomer having oneN-vinyl group. Optionally, the polymerizable composition of this examplecan comprise a vinyl-containing cross-linking agent.

In yet another example, the polymerizable composition of the presentdisclosure comprises a first siloxane monomer represented by formula(1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group, and the firstsiloxane monomer has a number average molecular weight of from 400daltons to 700 daltons. The polymerizable composition also comprises asecond siloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 7,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one hydrophilic amide-containing monomer having oneN-vinyl group. Optionally, the polymerizable composition of this examplealso comprises a vinyl-containing cross-linking agent.

In another example, the hydrophilic vinyl-containing monomer or monomercomponent can comprise or consist of a vinyl ether-containing monomer.Examples of vinyl ether-containing monomers include, without limitation,1,4-butanediol vinyl ether (BVE), or ethylene glycol vinyl ether (EGVE),or diethylene glycol vinyl ether (DEGVE), or any combination thereof. Inone example, the hydrophilic monomer component comprises or consists ofBVE. In another example, the hydrophilic monomer component comprises orconsists of EGVE. In yet another example, the hydrophilic vinylcomponent comprises or consists of DEGVE.

In yet another example, the hydrophilic vinyl-containing monomercomponent can comprise or consist of a combination of a firsthydrophilic monomer or monomer component, and a second hydrophilicmonomer or hydrophilic monomer component. In one example, the firsthydrophilic monomer has a different polymerizable functional group thanthe second hydrophilic monomer. In another example, each monomer of thefirst hydrophilic monomer has a different polymerizable functional groupthan the second hydrophilic monomer. In another example, the firsthydrophilic monomer has a different polymerizable functional group thaneach monomer of the second hydrophilic monomer component. In yet anotherexample, each monomer of the first hydrophilic monomer component has adifferent polymerizable functional group than each monomer of the secondhydrophilic monomer component.

For example, when the first hydrophilic monomer or monomer componentcomprises or consists of one or more amide-containing monomers, thesecond hydrophilic monomer or monomer component can comprise or consistof one or more non-amide monomers (i.e., one or more monomers each ofwhich do not have an amide functional group as part of their molecularstructures). As another example, when the first hydrophilic monomer ormonomer component comprises or consists of one or more vinyl-containingmonomers, the second hydrophilic monomer or monomer component cancomprise one or more non-vinyl monomers (i.e., one or more monomers eachof which do not have a vinyl polymerizable functional group as part oftheir molecular structures). In another example, when the firsthydrophilic monomer or monomer component comprises or consists of one ormore amide monomers each having an N-vinyl group, the second hydrophilicmonomer or monomer component can comprise or consist of one or morenon-amide monomers. When the first hydrophilic monomer or monomercomponent comprise or consists of one or more non-acrylate monomers(i.e., one or more monomers each of which do not have an acrylate ormethacrylate polymerizable functional group as part of their molecularstructures), the second hydrophilic monomer or monomer component cancomprise or consist of one or more acrylate-containing monomers, or oneor more methacrylate-containing monomers, or any combination thereof.When the first hydrophilic monomer or monomer components comprises orconsists of one or more non-vinyl ether-containing monomers (i.e., oneor more monomers each of which do not have a vinyl ether polymerizablefunctional group as part of their molecular structures), the secondhydrophilic monomer or monomer component can comprise or consist of oneor more vinyl ether-containing monomers. In a particular example, thefirst hydrophilic monomer or monomer component can comprise or consistof one or more amide-containing monomers each having an N-vinyl group,and the second hydrophilic monomer or monomer component can comprise orconsist of one or more vinyl ether-containing monomers.

In one example, when the first hydrophilic monomer or monomer componentcomprises or consists of a hydrophilic amide-containing monomer havingone N-vinyl group, the second hydrophilic monomer or monomer componentcan comprise or consist of a vinyl ether-containing monomer. In aparticular example, the first hydrophilic monomer can comprise VMA, andthe second hydrophilic monomer or monomer component can comprise BVE orEGVE or DEGVE or any combination thereof. The first hydrophilic monomercan comprise VMA and the second hydrophilic monomer can comprise BVE.The first hydrophilic monomer can comprise VMA and the secondhydrophilic monomer can comprise EGVE. The first hydrophilic monomer cancomprise VMA and the second hydrophilic monomer can comprise DEGVE. Thefirst hydrophilic monomer can comprise VMA, and the second hydrophilicmonomer component can comprise EGVE and DEGVE.

Similarly, the first hydrophilic monomer can be VMA, and the secondhydrophilic monomer or monomer component can comprise BVE or EGVE orDEGVE or any combination thereof. The first hydrophilic monomer can beVMA and the second hydrophilic monomer can be BVE. The first hydrophilicmonomer can be VMA and the second hydrophilic monomer can be EGVE. Thefirst hydrophilic monomer can comprise VMA and the second hydrophilicmonomer can be DEGVE. The first hydrophilic monomer can be VMA, and thesecond hydrophilic monomer component can be a combination of EGVE andDEGVE.

In another example, the non-silicon hydrophilic vinyl-containing monomercan have any molecular weight, such as a molecular weight less than 400daltons, or less than 300 daltons, or less than 250 daltons, or lessthan 200 daltons, or less than 150 daltons, or from about 75 to about200 daltons.

When a hydrophilic monomer or a hydrophilic monomer component is presentin the polymerizable composition, the hydrophilic monomer or monomercomponent can be present in the polymerizable composition in an amountfrom 30 to 60 unit parts of the polymerizable composition. Thehydrophilic monomer or monomer component can be present in thepolymerizable composition from 40 to 55 unit parts, or from 45 to 50unit parts by weight. When the hydrophilic monomer component of thepolymerizable composition comprises a first hydrophilic monomer ormonomer component and a second hydrophilic monomer or monomer component,the second hydrophilic monomer or monomer component can be present inthe polymerizable composition in an amount from 0.1 to 20 unit parts ofthe polymerizable composition. For example, of the total amount of from30 to 60 unit parts of hydrophilic monomer or monomer component presentin the polymerizable composition, 29.9 to 40 unit parts can comprise thefirst hydrophilic monomer or monomer component, and 0.1 to 20 unit partscan comprise the second hydrophilic monomer or monomer component. Inanother example, the second hydrophilic monomer or monomer component canbe present in the polymerizable composition from 1 to 15 unit parts, orfrom 2 to 10 unit parts, or from 3 to 7 unit parts.

In one example, the polymerizable composition of the present disclosurecomprises a first siloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one hydrophilic vinyl-containing monomer present inan amount from 30 unit parts to 60 unit parts. Optionally, thepolymerizable composition of this example can comprise avinyl-containing cross-linking agent

In another example, the polymerizable composition of the presentdisclosure comprises a first siloxane monomer represented by formula(1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one hydrophilic amide-containing monomer having oneN-vinyl group present in an amount from 30 unit parts to 60 unit parts.Optionally, the polymerizable composition of this example can comprise avinyl-containing cross-linking agent.

In yet another example, the polymerizable composition of the presentdisclosure comprises a first siloxane monomer represented by formula(1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group, and the firstsiloxane monomer has a number average molecular weight of from 400daltons to 700 daltons. The polymerizable composition also comprises asecond siloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 7,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one hydrophilic amide-containing monomer having oneN-vinyl group in an amount from 30 unit parts to 60 unit parts.Optionally, the polymerizable composition of this example also comprisesa vinyl-containing cross-linking agent.

As used herein, a vinyl-containing monomer is a monomer having a singlepolymerizable carbon-carbon double bond (i.e., a vinyl polymerizablefunctional group) present in its molecular structure, where, under freeradical polymerization, the carbon-carbon double bond in the vinylpolymerizable functional group is less reactive than the carbon-carbondouble bond present in an acrylate or a methacrylate polymerizablefunctional group. In other words, although a carbon-carbon double bondis present in acrylate groups and methacrylate groups, as understoodherein, monomers comprising a single acrylate or methacrylatepolymerizable group are not considered to be vinyl-containing monomers.Examples of polymerizable groups having carbon-carbon double bonds whichare less reactive than the carbon-carbon double bonds of acrylate ormethacrylate polymerizable groups include vinyl amide, vinyl ether,vinyl ester, and allyl ester polymerizable groups. Thus, as used herein,examples of vinyl-containing monomers include monomers having a singlevinyl amide, a single vinyl ether, a single vinyl ester, or a singleallyl ester polymerizable group.

In addition, the polymerizable compositions of the present disclosurecan optionally comprise at least one non-silicon hydrophobic monomer.The hydrophobic monomer is understood to be a non-silicone polymerizableingredient having only one polymerizable functional group present in itsmolecular structure. The at least one hydrophobic monomer of thepolymerizable composition can be one hydrophobic monomer, or cancomprise a hydrophobic monomer component composed of at least twohydrophobic monomers. Examples of hydrophobic monomers that can be usedin the polymerizable compositions disclosed herein, include, withoutlimitation, acrylate-containing hydrophobic monomers, ormethacrylate-containing hydrophobic monomers, or any combinationthereof. Examples of hydrophobic monomers include, without limitation,methyl acrylate, or ethyl acrylate, or propyl acrylate, or isopropylacrylate, or cyclohexyl acrylate, or 2-ethylhexyl acrylate, or methylmethacrylate (MMA), or ethyl methacrylate, or propyl methacrylate, orbutyl acrylate, or vinyl acetate, or vinyl propionate, or vinylbutyrate, or vinyl valerate, or styrene, or chloroprene, or vinylchloride, or vinylidene chloride, or acrylonitrile, or 1-butene, orbutadiene, or methacrylonitrile, or vinyltoluene, or vinyl ethyl ether,or perfluorohexylethylthiocarbonylaminoethyl methacrylate, or isobornylmethacrylate, or trifluoroethyl methacrylate, or hexafluoroisopropylmethacrylate, or hexafluorobutyl methacrylate, or ethylene glycol methylether methacrylate (EGMA), or any combination thereof. In one particularexample, the hydrophobic monomer or monomer component can comprise orconsist of MMA, or EGMA, or both.

When present in the polymerizable composition, the hydrophobic monomeror monomer component can be present in an amount from about 5 to about25 unit parts, or from about 10 to about 20 unit parts.

In one example, the hydrophobic monomer component can comprise at leasttwo hydrophobic monomers each having different polymerizable functionalgroups. In another example, the hydrophobic monomer component cancomprise at least two hydrophobic monomers each having the samepolymerizable functional group. The hydrophobic monomer component cancomprise or consist of two hydrophobic monomers, both having the samepolymerizable functional group. In one example, the hydrophobic monomercomponent can comprise or consist of two hydrophobicmethacrylate-containing monomers. The hydrophobic monomer component cancomprise or consist of MMA and EGMA. In one example, the at least twohydrophobic monomers of the hydrophobic monomer component can compriseor consist of MMA and EGMA, and the ratio of the unit parts of MMA tothe unit parts of EGMA present in the polymerizable composition can befrom about 6:1 to about 1:1. The ratio of the unit parts of MMA and EGMApresent in the polymerizable composition can be about 2:1 based on theunit parts of MMA to the unit parts of EGMA.

Optionally, the polymerizable composition can further comprise at leastone cross-linking agent. The polymerizable composition can comprise onecross-linking agent, or can comprise a cross-linking agent componentcomprised of at least two cross-linking agents. As used herein, across-linking agent is a non-silicon cross-linking agent and thus isdifferent from multifunctional siloxane monomers which may be present inthe polymerizable compositions.

In accordance with the present disclosure, a cross-linking agent isunderstood to be a monomer having more than one polymerizable functionalgroup as part of its molecular structure, such as two or three or fourpolymerizable functional groups, i.e., a multifunctional monomer such asa bifunctional or trifunctional or tetrafunctional monomer. Non-siliconcross-linking agents that can be used in the polymerizable compositionsdisclosed herein include, for example, without limitation, allyl(meth)acrylate, or lower alkylene glycol di(meth)acrylate, or poly(loweralkylene) glycol di(meth)acrylate, or lower alkylene di(meth)acrylate,or divinyl ether, or divinyl sulfone, or di- and trivinylbenzene, ortrimethylolpropane tri(meth)acrylate, or pentaerythritoltetra(meth)acrylate, or bisphenol A di(meth)acrylate, ormethylenebis(meth)acrylamide, or triallyl phthalate and diallylphthalate, or any combination thereof. Cross-linking agents, asdisclosed in Examples C1 and 1-25, include, for example, ethylene glycoldimethacrylate (EGDMA), or triethylene glycol dimethacrylate (TEGDMA),or triethylene glycol divinyl ether (TEGDVE), or any combinationthereof. In one example, the cross-linking agent can have a molecularweight less than 1500 daltons, or less than 1000 daltons, or less than500 daltons, or less than 200 daltons.

In one example, the cross-linking agent can be a vinyl-containingcross-linking agent. As used herein, a vinyl-containing cross-linkingagent is a monomer having at least two polymerizable carbon-carbondouble bonds (i.e., at least two vinyl polymerizable functional groups)present in its molecular structure, where each of the at least twopolymerizable carbon-carbon double bonds present in the vinylpolymerizable functional groups of the vinyl-containing cross-linkingagent is less reactive than a carbon-carbon double bond present in anacrylate or methacrylate polymerizable functional group. Althoughcarbon-carbon double bonds are present in acrylate and methacrylatepolymerizable functional groups, as understood herein, cross-linkingagents comprising one or more acrylate or methacrylate polymerizablegroup (e.g., an acrylate-containing cross-linking agent or amethacrylate-containing cross-linking agent) are not considered to bevinyl-containing cross-linking agents. Polymerizable functional groupshaving carbon-carbon double bonds which are less reactive than thecarbon-carbon double bonds of acrylate or methacrylate polymerizablegroups include, for example, vinyl amide, vinyl ester, vinyl ether andallyl ester polymerizable functional groups. Thus, as used herein,vinyl-containing cross-linking agents include, for example,cross-linking agents having at least two polymerizable functional groupsselected from a vinyl amide, a vinyl ether, a vinyl ester, an allylester, and any combination thereof. As used herein, a mixedvinyl-containing cross-linking agent is a cross-linking agent having atleast one polymerizable carbon-carbon double bond (i.e., at least onevinyl polymerizable functional group) present in its structure which isless reactive than the carbon-carbon double bond present in an acrylateor methacrylate polymerizable functional group, and at least onepolymerizable functional group present in its structure having acarbon-carbon double bond which is at least as reactive as thecarbon-carbon double bond in an acrylate or methacrylate polymerizablefunctional group.

In one example, the cross-linking agent or cross-linking agent componentcan comprise a vinyl-containing cross-linking agent. For example, thevinyl-containing cross-linking agent or cross-linking agent componentcan comprise or consist of a vinyl ether-containing cross-linking agent.In another example, the cross-linking agent or cross-linking agentcomponent can comprise or consist of an acrylate-containingcross-linking agent (i.e., a cross-linking agent having at least twoacrylate polymerizable functional groups), or a methacrylate-containingcross-linking agent (i.e., at least two methacrylate polymerizablefunctional groups), or at least one acrylate-containing cross-linkingagent and at least one methacrylate-containing cross-linking agent.

The cross-linking agent component can comprise or consist of acombination of two or more cross-linking agents, each of which has adifferent polymerizable functional group. For example, the cross-linkingagent component can comprise one vinyl-containing cross-linking agent,and one acrylate-containing cross-linking agent. The cross-linking agentcomponent can comprise one vinyl-containing cross-linking agent and onemethacrylate-containing cross-linking group. The cross-linking agentcomponent can comprise or consist of one vinyl ether-containingcross-linking agent, and one methacrylate-containing cross-linkingagent.

Optionally, the polymerizable composition of the present disclosure cancomprise or consist of at least one vinyl-containing cross-linking agentor cross-linking agent component, and can be free of a non-siliconnon-vinyl crosslinking agent. In other words, in this example, thepolymerizable composition comprises the first siloxane monomer, thesecond siloxane monomer, and at least one cross-linking agent, whereinthe at least one cross-linking agent consists of at least onevinyl-containing cross-linking agent (i.e., a single vinyl-containingcross-linking agent or a vinyl-containing cross-linking agent componentcomprised of two or more vinyl-containing cross-linking agents), as nonon-silicone cross-linking agents other than vinyl-containingcross-linking agents are present in the polymerizable composition. Inother words, in this example, no non-vinyl cross-linking agents arepresent in the polymerizable composition.

In one example, the polymerizable composition of the present disclosurecomprises a first siloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one vinyl-containing cross-linking agent. In anotherexample, the polymerizable composition of the present disclosurecomprises a first siloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises a cross-linking agent component comprising at least onevinyl-containing cross-linking agent and at least oneacrylate-containing cross-linking agent.

In yet another example, the polymerizable composition of the presentdisclosure comprises a first siloxane monomer represented by formula(1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group, and the firstsiloxane monomer has a number average molecular weight of from 400daltons to 700 daltons. The polymerizable composition also comprises asecond siloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 7,000 daltons.The first siloxane monomer and the second siloxane monomer are presentin the polymerizable composition in a ratio of at least 2:1 based onunit parts by weight. The polymerizable composition of this example alsocomprises at least one hydrophilic amide-containing monomer having oneN-vinyl group in an amount from 30 unit parts to 60 unit parts, andcomprises a cross-linking agent component comprising at least onevinyl-containing cross-linking agent and at least oneacrylate-containing cross-linking agent.

The optional cross-linking agent or cross-linking agent component can bepresent in the polymerizable composition in an amount from 0.01 to 10.0unit parts, such as, for example, from 0.05 to 5.0 unit parts, or from0.1 to 2.0 unit parts, or from 0.2 to 1.0 unit parts, or from 0.3 to 0.8unit parts. In one example, when the cross-linking agent orcross-linking agent component comprises a vinyl-containing cross-linkingagent, the vinyl-containing cross-linking agent or cross-linking agentcomponent can be present in the polymerizable composition in an amountfrom 0.01 to 0.50 unit parts, such as, for example, 0.05 to 0.30 unitparts or from 0.1 to 0.2 unit parts. When the at least one cross-linkingagent is a acrylate-containing or methacrylate-containing cross-linkingagent or cross-linking agent component, the acrylate-containing ormethacrylate-containing cross-linking agent or cross-linking agentcomponent can be present in the polymerizable composition in an amountfrom 0.1 to 2.0 unit parts, such as, for example, 0.3 to 1.2 unit partsor from 0.5 to 0.8 unit parts. When a combination of a vinyl-containingcross-linking agent or crosslinking agent component, and anacrylate-containing or methacrylate-containing cross-linking agent orcross-linking agent component is used, the vinyl-containingcross-linking agent or cross-linking agent component and theacrylate-containing or methacrylate-containing cross-linking agent orcross-linking agent component can be present in the polymerizablecomposition in a ratio from 1:2 to 1:20, or from 1:3 to 1:12, or from1:4 to 1:7 based on the ratio by weight of the unit parts of thevinyl-containing cross-linking agent or cross-linking agent component tothe unit parts of the acrylate-containing or methacrylate-containingcross-linking agent or cross-linking component.

The polymerizable composition can optionally include one or more organicdiluents, one or more polymerization initiators (i.e., ultraviolet (UV)initiators or thermal initiators, or both), or one or more UV absorbingagents, or one or more tinting agents, or one or more oxygen scavengers,or one or more chain transfer agents, or any combination thereof. Theseoptional ingredients can be reactive or non-reactive ingredients. In oneexample, the polymerizable compositions can be diluent-free in that theydo not contain any organic diluent to achieve miscibility between thesiloxanes and the other lens forming ingredients, such as the optionalhydrophilic monomers, hydrophobic monomer, and cross-linking agents. Inaddition, many of the present polymerizable compositions are essentiallyfree of water (e.g., contain no more than 3.0% or 2.0% water by weight).

The polymerizable compositions disclosed herein can optionally compriseone or more organic diluents, i.e., the polymerizable composition cancomprise an organic diluent, or can comprise an organic diluentcomponent comprising two or more organic diluents. Organic diluents thatcan optionally be included in the present polymerizable compositionsinclude alcohols, including lower alcohols, such as, for example,without limitation, pentanol, or hexanol, or octanol, or decanol, or anycombination thereof. When included, the organic diluent or organicdiluent component can be provided in the polymerizable composition in anamount from about 1 to about 70 unit parts, or from about 2 unit partsto about 50 unit parts, or from about 5 unit parts to about 30 unitparts.

Approaches commonly employed to increase the miscibility of siloxanemonomers and hydrophilic monomers include adding organic diluents to thepolymerizable composition to act as compatiblizers between thehydrophilic monomers and the siloxane monomers which typically are morehydrophobic, or using only siloxane monomers having low molecularweights (e.g., molecular weights below 2500 daltons). The use of thefirst siloxane as described above makes it possible to include both ahigh molecular weight second siloxane and a high level of one or morehydrophilic monomers in the polymerizable compositions of the presentdisclosure. And while it is possible to include one or more organicdiluents in the present polymerizable compositions disclosed herein, itmay not be necessary to do so in order to obtain a misciblepolymerizable composition in accordance with the present disclosure. Inother words, in one example, the silicone hydrogel contact lenses of thepresent disclosure are formed from polymerizable compositions which arefree of an organic diluent.

An example of the disclosed polymerizable composition can be misciblewhen initially prepared, and can remain miscible over a period of timeadequate for the commercial manufacture of contact lenses, such as, forexample, for 2 weeks, or 1 week, or 5 days. Typically, when polymerizedand processed into contact lenses, miscible polymerizable compositionsresult in contact lenses having ophthalmically acceptable clarities.

The present polymerizable compositions can optionally comprise one ormore polymerization initiators, i.e., the polymerizable composition cancomprise an initiator, or can comprise an initiator component comprisingtwo or more polymerization initiators. Polymerization initiators thatcan be included in the present polymerizable compositions include, forexample, azo compounds, or organic peroxides, or both. Initiators thatcan be present in the polymerizable composition include, for example,without limitation, benzoin ethyl ether, or benzyl dimethyl ketal, oralpha, alpha-diethoxyacetophenone, or 2,4,6-trimethylbenzoyl diphenylphosphine oxide, or benzoin peroxide, or t-butyl peroxide, orazobisisobutyronitorile, or azobisdimethylvaleronitorile, or anycombination thereof. UV photoinitiators can include, for example,phosphine oxides such as diphenyl (2,4,6-trimethyl benzoyl) phosphineoxide, or benzoin methyl ether, or 1-hydroxycyclohexylphenyl ketone, orDarocur (available from BASF, Florham Park, N.J., USA), or Irgacur (alsoavailable from BASF), or any combination thereof. In many of Examples C1and 1-25 disclosed herein, the polymerization initiator is the thermalinitiator 2,2′-azobis-2-methyl propanenitrile (VAZO-64 from E.I. DuPontde Nemours & Co., Wilmington, Del., USA). Other commonly usedthermoinitiators can include 2,2′-azobis(2,4-dimethylpentanenitrile)(VAZO-52) and 1,1′-azo bis(cyanocyclohexane) (VAZO-88). Thepolymerization initiator or initiator component can be present in thepolymerizable composition in an amount from about 0.01 unit parts toabout 2.0 unit parts, or in an amount from about 0.1 unit parts to about1.0 unit parts, or from about 0.2 unit parts to about 0.6 unit parts byweight.

Optionally, the present polymerizable compositions can comprise one ormore UV absorbing agents, i.e., the polymerizable composition cancomprise an UV absorbing agent, or can comprise an UV absorbing agentcomponent comprising two or more UV absorbing agents. UV absorbingagents that can be included in the present polymerizable compositionsinclude, for example, benzophenones, or benzotriazoles, or anycombination thereof. In many of Examples C1 and 1-25 disclosed herein,the UV absorbing agent is 2-(4-Benzoyl-3-hydroxyphenoxy)ethyl acrylate(UV-416) or 2-(3-(2H-benzotriazol-2-YL)-4-hydroxy-phenyl)ethylmethacrylate (NORBLOC® 7966 from Noramco, Athens, Ga., USA). The UVabsorbing agent or UV absorbing agent component can be present in thepolymerizable composition in an amount from about 0.01 unit parts toabout 5.0 unit parts, or in an amount from about 0.1 unit parts to about3.0 unit parts, or from about 0.2 unit parts to about 2.0 unit parts byweight.

The polymerizable compositions of the present disclosure can alsooptionally include at least one tinting agent (i.e., one tinting agentor a tinting agent component comprising two or more tinting agents),although both tinted and clear lens products are contemplated. In oneexample, the tinting agent can be a reactive dye or pigment effective toprovide color to the resulting lens product. The tinting agent ortinting agent component of the polymerizable composition can comprise apolymerizable tinting agent, or can comprise a non-polymerizable tintingagent, or any combination thereof. The polymerizable tinting agent canbe a tinting agent whose molecular structure comprises a polymerizablefunctional group, or can be a tinting agent whose molecular structureincludes both a monomer portion and a dye portion, i.e., the tintingagent can be a monomer-dye compound. The molecular structure of thetinting agent can comprise a beta sulfone functional group, or cancomprise a triazine functional group. Tinting agents can include, forexample, VAT Blue 6(7,16-Dichloro-6,15-dihydroanthrazine-5,9,14,18-tetrone), or1-Amino-4-[3-(beta-sulfatoethylsulfonyl)anilio]-2-anthraquinonesulfonicacid (C. I. Reactive Blue 19, RB-19), or a monomer-dye compound ofReactive Blue 19 and hydroxyethylmethacrylate (RB-19 HEMA), or1,4-bis[4-[(2-methacryl-oxyethyl)phenylamino]anthraquinone (ReactiveBlue 246, RB-246, available from Arran Chemical Company, Athlone,Ireland), or 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedionebis(2-propenoic)ester (RB-247), or Reactive Blue 4, RB-4, or amonomer-dye compound of Reactive Blue 4 and hydroxyethyl methacrylate(RB-4 HEMA or “Blue HEMA”), or any combination thereof. In one example,the tinting agent or tinting agent component can comprise apolymerizable tinting agent. The polymerizable tinting agent componentcan comprise, for example, RB-246, or RB-274, or RB-4 HEMA, or RB-19HEMA, or any combination thereof. Examples of monomer-dye compoundsinclude RB-4 HEMA and RB-19 HEMA. Additional examples of monomer-dyecompounds are described in U.S. Pat. No. 5,944,853 and U.S. Pat. No.7,216,975, both of which are incorporated in their entirety by referenceherein. Other exemplary tinting agents are disclosed, for example, inU.S. Patent Application Publication No. 2008/0048350, the disclosure ofwhich is incorporated in its entirety herein by reference. In many ofExamples C1 and 1-25 disclosed herein, the tinting agent is a reactiveblue dye, such as those described in U.S. Pat. No. 4,997,897, thedisclosure of which is incorporated in its entirety herein by reference.Other suitable tinting agents for use in accordance with the presentinvention are phthalocyanine pigments such as phthalocyanine blue, orphthalocyanine green, or chromic-alumina-cobaltous oxide, or chromiumoxides, or various iron oxides for red, yellow, brown and black colors,or any combination thereof. Opaquing agents such as titanium dioxide canalso be incorporated. For certain applications, a combination of tintingagents having different colors can be employed as the tinting agentcomponent. If employed, the tinting agent or tinting agent component canbe present in the polymerizable composition in an amount ranging fromabout 0.001 unit parts to about 15.0 unit parts, or about 0.005 unitparts to about 10.0 unit parts, or about 0.01 unit parts to about 8.0unit parts.

The polymerizable compositions of the present disclosure can optionallycomprise at least one oxygen scavenger, i.e., one oxygen scavenger or anoxygen scavenger component comprising two or more oxygen scavengers.Examples of oxygen scavengers which can be included as the oxygenscavenger or oxygen scavenger component of the present polymerizablecompositions include, for example, Vitamin E, or phenolic compounds, orphosphite compounds, or phosphine compounds, or amine oxide compounds,or any combination thereof. For example, the oxygen scavenger or oxygenscavenger component can consist of or comprise a phosphine-containingcompound. In many of Examples C1 and 1-25 disclosed herein, the oxygenscavenger or oxygen scavenger component is a phosphine-containingcompound, such as triphenyl phosphine, or a polymerizable form oftriphenyl phosphine, such as diphenyl(P-vinylphenyl)phosphine.

Chain transfer is a polymerization reaction in which the activity of agrowing polymer chain is transferred to another molecule, reducing theaverage molecular weight of the final polymer. The polymerizablecompositions of the present disclosure can optionally comprise at leastone chain transfer agent, i.e., can comprise one chain transfer agent orcan comprise a chain transfer agent component comprising at least twochain transfer agents. Examples of chain transfer agents which can beincluded as the chain transfer agent or the chain transfer component ofthe present polymerizable compositions include, for example, thiolcompounds, or halocarbon compounds, or C3-C5 hydrocarbons, or anycombination thereof. In many of Examples C1 and 1-25 disclosed herein,the chain transfer agent is allyloxy ethanol. When present in thepolymerizable composition, the chain transfer agent or chain transferagent component can be present in an amount from about 0.01 unit partsto about 1.5 unit parts, for example from about 0.1 unit parts to about0.5 unit parts.

In one example, the silicone hydrogel contact lenses of the presentdisclosure can have high equilibrium water contents (EWC)s. Methods ofdetermining EWC are known to those of ordinary skill in the art, and canbe based on weight loss from a lens during a drying process. Forexample, the silicone hydrogel contact lenses can have, when fullyhydrated, an equilibrium water content from 20% to 75% by weight. Thepresent contact lenses can have an EWC from about 30% to about 70%, orfrom about 45% to about 65%, or from about 50% to about 63%, or fromabout 50% to about 67%, or from about 55% to about 65% by weight.

The present contact lenses can have an oxygen permeability (or Dk) of atleast 55 barrers (Dk≧55 barrers), or an oxygen permeability of at least60 barrers (Dk≧60 barrers), or an oxygen permeability of at least 65barrers (Dk≧65 barrers). The lenses can have an oxygen permeability fromabout 55 barrers to about 135 barrers, or from about 60 barrers to about120 barrers, or from about 65 barrers to about 90 barrers, or from about50 barrers to about 75 barrers. Various methods of determining oxygenpermeability are known to those of ordinary skill in the art.

The silicone hydrogel contact lenses of the present disclosure have,when fully hydrated, an average tensile modulus about 0.20 MPa to about0.90 MPa. For example, the average modulus can be from about 0.30 MPa toabout 0.80 MPa, or from about 0.40 MPa to about 0.75 MPa, or from about0.50 MPa to about 0.70 MPa.

As used herein, the modulus of a contact lens or lens body is understoodto refer to the tensile modulus, also know as Young's modulus. It is ameasure of the stiffness of an elastic material. The tensile modulus canbe measured using a method in accordance with ANSI Z80.20 standard. Inone example, the tensile modulus can be measured using an Instron Model3342 or Model 3343 mechanical testing system.

The present contact lenses can have an oxygen permeability of at least55 barrers (Dk≧55 barrers), or an EWC from about 30% to about 70%, or atensile modulus from about 0.2 MPa to about 0.9 MPa, or any combinationthereof. In one example, the contact lenses can have an oxygenpermeability of at least 60 barrers (Dk≧60 barrers), or an EWC fromabout 35% to about 65%, or a tensile modulus from about 0.3 MPa to about0.8 MPa, or any combination thereof. In another example, the presentcontact lenses can have an oxygen permeability of at least 60 barrers,or an EWC from about 45% to about 65%, or a tensile modulus from about0.40 MPa to about 0.75 MPa, or any combination thereof.

In one example, the present contact lenses have an oxygen permeabilityof at least 55 barrers, an EWC from about 30% to about 70%, and atensile modulus from about 0.2 MPa to about 0.9 MPa.

The silicone hydrogel contact lenses of the present disclosure can have,when fully hydrated, an average percentage of energy loss from about 25%to about 40%. For example, the average percentage of energy loss can befrom about 27% to about 40%, or can be from about 30% to about 37%.

As used herein, percentage of energy loss is a measure of the energylost as heat when energy loading and unloading cycles are applied toviscoelastic materials. Percentage of energy loss can be determinedusing a number of methods known to those of ordinary skill in the art.For example, the force involved in stretching a sample to 100% strain,and then returning it to 0% at a constant rate can be determined andused to calculate the percentage energy loss for the material.

The present contact lenses can have an ionoflux less than about 8.0×10⁻³mm²/min, or less than about 7.0×10⁻³ mm²/min, or less than about5.0×10⁻³ mm²/min. Various methods of determining ionoflux areconventional and are known to those of ordinary skill in the art.

Silicone hydrogel contact lenses of the present invention can havecaptive bubble dynamic advancing contact angles of less than 120degrees, such as, for example, less than 90 degrees when fully hydrated,less than 80 degrees when fully hydrated, less than 70 degrees whenfully hydrated, or less than 65 degrees when fully hydrated, or lessthan 60 degrees when fully hydrated, or less than 50 degrees when fullyhydrated.

Silicone hydrogel contact lenses of the present invention can havecaptive bubble static contact angles of less than 70 degrees when fullyhydrated, or less than 60 degrees when fully hydrated, or less than 55degrees when fully hydrated, or less than 50 degrees when fullyhydrated, or less than 45 degrees when fully hydrated.

In one example, the present contact lenses can have a wet extractablecomponent. The wet extractable component is determined based on theweight lost during methanol extraction of contact lenses which have beenfully hydrated and sterilized prior to drying and extraction testing.The wet extractable component can comprise unreacted or partiallyreacted polymerizable ingredients of the polymerizable composition. Thewet extractable component consists of organic solvent-extractablematerials remaining in the lens body after the lens body has been fullyprocessed to form a sterilized contact lens, for lenses formed frompolymerizable compositions comprising non-polymerizable ingredients. Forlenses extracted during manufacturing in either an extraction liquidcomprising a volatile organic solvent or an extraction liquid free of anorganic solvent, in most cases, substantially all of thenon-polymerizable ingredients will have been removed from the lens body,and so the wet extractable component may consist essentially ofextractable components formed from reactive polymerizable ingredients ofthe polymerizable composition, i.e., unreacted polymerizable componentsand partially reacted polymerizable ingredients. In lenses made from apolymerizable composition free of a diluent, the wet extractablecomponent can be present in the contact lens in an amount from about 1%wt/wt to about 15% wt/wt, or from about 2% wt/wt to about 10% wt/wt, orfrom about 3% wt/wt to about 8% wt/wt based on the dry weight of thelens body prior to extraction testing. In lenses made from apolymerizable composition comprising a diluent, the wet extractablecomponent may consist of a portion of the diluent as well as unreactedand partially reacted polymerizable ingredients, and can be present inthe contact lens in an amount from about 1% wt/wt to about 20% wt/wt, orfrom about 2% wt/wt to about 15% wt/wt of the lens, or from about 3%wt/wt to about 10% wt/wt based on the dry weight of the lens body priorto extraction testing.

In one example, the present contact lenses have a dry extractablecomponent. The dry extractable component is determined based on theweight lost during extraction in methanol of polymeric lens bodies whichhave not been washed, extracted (as part of a manufacturing process),hydrated or sterilized prior to the drying and extraction testing. Thedry extractable component can comprise unreacted or partially reactedpolymerizable ingredients of the polymerizable composition. Whenoptional non-polymerizable ingredients such as diluents and the like arepresent in the polymerizable composition, the dry extractable componentmay further comprise the non-polymerizable ingredients.

In lenses made from a polymerizable composition free of a diluent, thedry extractable component of the lens consists primarily of dryextractable components contributed by polymerizable ingredients of thepolymerizable composition (i.e., unreacted or partially reactedpolymerizable ingredients), and may also include dry extractablematerials contributed by optional non-polymerizable components presentin the polymerizable composition in small amounts (e.g., less than 3%wt/wt), such as, for example, tinting agents, oxygen scavengers, and thelike. In lenses made from a polymerizable composition free of a diluent,the dry extractable component can be present in the polymeric lens bodyin an amount from about 1% wt/wt to about 30% wt/wt of the lens body, orfrom about 2% wt/wt to about 25% wt/wt, or from about 3% wt/wt to about20% wt/wt, or from about 4% wt/wt to about 15% wt/wt, or from 2% wt/wtto less than 10% wt/wt based on the dry weight of the lens body prior toextraction testing.

In lenses made from a polymerizable composition comprising a largeamount (e.g., more than 3% wt/wt) of an optional non-polymerizableingredient such as a diluent, the dry extractable component consists ofextractable materials contributed by reactive ingredients as well asextractable components contributed by non-polymerizable ingredients ofthe polymerizable composition. The total amount of dry extractablecomponents contributed by reactive ingredients and non-polymerizableingredients present in the contact lens can consist of an amount fromabout 1% wt/wt to about 75% wt/wt, or from about 2% wt/wt to about 50%wt/wt of the lens, or from about 3% wt/wt to about 40% wt/wt, or fromabout 4% wt/wt to about 20% wt/wt, or from about 5% to about 10% basedon the dry weight of the polymeric lens body prior to extractiontesting. The total amount of dry extractable components contributed bypolymerizable ingredients (i.e., unreacted or partially reactedpolymerizable ingredients) can be an amount from about 1% wt/wt to about30% wt/wt of the lens body, or from about 2% wt/wt to about 25% wt/wt,or from about 3% wt/wt to about 20% wt/wt, or from about 4% wt/wt toabout 15% wt/wt, or from 2% wt/wt to less than 10% wt/wt based on thedry weight of the lens body prior to extraction testing.

The contact lenses of the present disclosure, as they are configured tobe placed or disposed on a cornea of an animal or human eye, areophthalmically acceptable contact lenses. As used herein, anophthalmically acceptable contact lens is understood to be a contactlens having at least one of a number of different properties asdescribed below. An ophthalmically acceptable contact lens can be formedof, and packaged in, ophthalmically acceptable ingredients such that thelens is not cytotoxic and does not release irritating and/or toxicingredients during wear. An ophthalmically acceptable contact lens canhave a level of clarity in the optic zone of the lens (i.e., the portionof the lens providing vision correction) sufficient for its intended usein contact with the cornea of an eye, for example, a transmittance of atleast 80%, or at least 90%, or at least 95% of visible light. Anophthalmically acceptable contact lens can have sufficient mechanicalproperties to facilitate lens handling and care for a duration of timebased on its intended lifetime. For example, its modulus, tensilestrength, and elongation can be sufficient to withstand insertion, wear,removal and, optionally, cleaning over the intended lifetime of thelens. The level of these properties which are appropriate will varydepending upon the intended lifetime and usage of the lens (e.g., singleuse daily disposable, multiple use monthly, etc). An ophthalmicallyacceptable contact lens can have an effective or appropriate ionoflux tosubstantially inhibit or substantially prevent corneal staining, such ascorneal staining more severe than superficial or moderate cornealstaining after continuous wear of the lens on a cornea for 8 or morehours. An ophthalmically acceptable contact lens can have a level ofoxygen permeability sufficient to allow oxygen to reach the cornea of aneye wearing the lens in an amount sufficient for long term cornealhealth. An ophthalmically acceptable contact lens can be a lens whichdoes not cause substantial or undue corneal swelling in an eye wearingthe lens, for example, no more than about 5% or 10% corneal swellingafter being worn on a cornea of an eye during an overnight sleep. Anophthalmically acceptable contact lens can be a lens which allowsmovement of the lens on the cornea of an eye wearing the lens sufficientto facilitate tear flow between the lens and the eye, in other words,does not cause the lens to adhere to the eye with sufficient force toprevent normal lens movement, and that has a low enough level ofmovement on the eye to allow vision correction. An ophthalmicallyacceptable contact lens can be a lens which allows wearing of the lenson the eye without undue or significant discomfort and/or irritationand/or pain. An ophthalmically acceptable contact lens can be a lenswhich inhibits or substantially prevents lipid and/or protein depositionsufficient to cause the lens wearer to remove the lens because of suchdeposits. An ophthalmically acceptable contact lens can have at leastone of a water content, or a surface wettability, or a modulus or adesign, or any combination thereof, that is effective to facilitateophthalmically compatible wearing of the contact lens by a contact lenswearer at least for one day. Ophthalmically compatible wearing isunderstood to refer to the wearing of a lens by a lens wearer withlittle or no discomfort, and with little or no occurrence of cornealstaining. Determining whether a contact lens is ophthalmicallyacceptable can be achieved using conventional clinical methods, such asthose performed by an eye care practitioner, and as understood bypersons of ordinary skill in the art.

In one example of the present disclosure, the contact lens can haveophthalmically acceptably wettable lens surfaces. For example, thecontact lens can have ophthalmically acceptably wettable lens surfaceswhen the polymerizable composition used to form the lens is free of awetting agent, or when the polymerizable composition used to form thelens is free of an organic diluent, or when the polymeric lens body isfree of a wetting agent, or when the polymeric lens body is washed,extracted and hydrated in extraction liquid free of a volatile organicsolvent, or when the lens is free of a surface treatment or surfacemodification, or any combination thereof. The contact lens can have theophthalmically acceptably wettable lens surfaces when the polymerizablecomposition used to form the lens is free of an internal wetting agent,or when the polymerizable composition used to form the lens is free ofan organic diluent, or when the polymeric lens body is only contacted byliquids free of volatile organic solvents during manufacturing, or whenthe polymeric lens body is free of a surface plasma treatment, or anycombination thereof.

One approach commonly used in the art to increase the wettability ofcontact lens surfaces is to apply treatments to the lens surfaces or tomodify the lens surfaces. In accordance with the present disclosure, thesilicone hydrogel contact lenses can have ophthalmically acceptablywettable lens surfaces without the presence of a surface treatment orsurface modification. Surface treatments include, for example, plasmaand corona treatments which increase the hydrophilicity of the lenssurface. While it is possible to apply one or more surface plasmatreatments to the present lens bodies, it is not necessary to do so inorder to obtain a silicone hydrogel contact lens having ophthalmicallyacceptably wettable lens surfaces when fully hydrated. In other words,in one example, the silicone hydrogel contact lenses of the presentdisclosure can be can be free of a surface plasma or corona treatment.

Surface modifications include binding wetting agents to the lenssurface, such as, for example, binding a wetting agent such as ahydrophilic polymer to at least a lens surface by chemical bonding oranother form of chemical interaction. In some cases, the wetting agentmay be bound to the lens surface as well as a least a portion of thepolymeric matrix of the lens, i.e., at least a portion of the bulk ofthe lens, by chemical bonding or another form of chemical interaction.The ophthalmically acceptably wettable lens surfaces of the presentdisclosure can be ophthalmically acceptably wettable without thepresence of a wetting agent (e.g., a polymeric material or anon-polymeric material) bound to at least the lens surface. While it ispossible to bind one or more wetting agents to the present lenses, it isnot necessary to do so in order to obtain a silicone hydrogel contactlens having ophthalmically acceptably wettable lens surfaces when fullyhydrated. Thus, in one example, the lenses of the present disclosure cancomprise wetting agents, such as, for example, hydrophilic polymers andincluding polyvinyl pyrrolidone, bound to a surface of the lens.Alternatively, in another example, the silicone hydrogel contact lensesof the present disclosure can be free of a wetting agent bound to thelens surface.

Another method of increasing lens wettability is to physically entrap awetting agent within the lens body or contact lens, such as byintroducing the wetting agent into the lens body when the lens body isswollen, and then returning the lens body to a less swollen state,thereby entrapping a portion of a wetting agent within the lens body.The wetting agent can be permanently trapped within the lens body, orcan be released from the lens over time, such as during wear. Theophthalmically acceptably wettable lens surfaces of the presentdisclosure can be ophthalmically acceptably wettable without thepresence of a wetting agent (e.g., a polymeric material or anon-polymeric material) physically entrapped in the lens body followingformation of the polymeric lens body. While it is possible to physicallyentrap one or more wetting agents in the present lenses, it is notnecessary to do so in order to obtain a silicone hydrogel contact lenshaving ophthalmically acceptably wettable lens surfaces when fullyhydrated. Thus, in one example, the lenses of the present disclosure cancomprise wetting agents, such as, for example, hydrophilic polymers andincluding polyvinyl pyrrolidone, entrapped within the lenses.Alternatively, the silicone hydrogel contact lenses of the presentdisclosure can be free of a wetting agent physically entrapped withinthe lens. As used herein, physically entrapped refers to immobilizing awetting agent, or other ingredient, in the polymeric matrix of the lenswith little or no chemical bonding or chemical interaction being presentbetween the wetting agent and or other ingredient and the polymericmatrix. This is in contrast to ingredients that are chemically bound tothe polymeric matrix, such as by ionic bonds, covalent bonds, van derWaals forces, and the like.

Another approach commonly used in the art to increase the wettability ofsilicone hydrogel contact lenses includes adding one or more wettingagents to the polymerizable composition. In one example, the wettingagent can be a polymeric wetting agent. However, the contact lenses ofthe present disclosure can have ophthalmically acceptably wettable lenssurfaces when the polymerizable composition used to form the polymericlens body is free of a wetting agent. While it is possible to includeone or more wetting agents in the present polymerizable compositions toincrease the wettability of the silicone hydrogel contact lenses of thepresent disclosure, it is not necessary to do so in order to obtain asilicone hydrogel contact lens having ophthalmically acceptably wettablelens surfaces. In other words, in one example, the silicone hydrogelcontact lenses of the present disclosure can be formed frompolymerizable compositions free of wetting agents. Alternatively, inanother example, the polymerizable compositions of the present inventioncan further comprise a wetting agent.

In one example, the wetting agent can be an internal wetting agent. Theinternal wetting agent can be bound within at least a portion of thepolymeric matrix of the lens. For example, the internal wetting agentcan be bound within at least a portion of the polymeric matrix of thelens by chemical bonding or another form of chemical interaction. Insome cases, the wetting agent may be bound to the lens surface as well.The internal wetting agent can comprise a polymeric material or anon-polymeric material. While it is possible to bind one or moreinternal wetting agents within the polymeric matrix of the presentlenses, it is not necessary to do so in order to obtain a siliconehydrogel contact lens having ophthalmically acceptably wettable lenssurfaces when fully hydrated. Thus, in one example, the lenses of thepresent disclosure can comprise internal wetting agents bound to atleast a portion of the polymeric matrix of the lens. Alternatively, inanother example, the silicone hydrogel contact lenses of the presentdisclosure can be free of an internal wetting agent bound to at least aportion of the polymeric matrix of the lens.

In another example, the wetting agent can be an internal polymericwetting agent. The internal polymeric wetting agent can be present inthe polymeric lens body as part of an interpenetrating polymer network(IPN) or a semi-IPN. An interpenetrating polymer network is formed by atleast two polymers, each of which is crosslinked to itself, but none ofwhich are crosslinked to each other. Similarly, a semi-IPN is formed byat least two polymers, at least one of which is crosslinked to itselfbut not to the other polymer, and the other of which is not crosslinkedeither to itself or the other polymer. In one example of the presentdisclosure, the contact lens can have ophthalmically acceptably wettablelens surfaces when the polymeric lens body is free of an internalpolymeric wetting agent present in the lens body as an IPN or asemi-IPN. Alternatively, the contact lens can comprise an internalpolymeric wetting agent present in the lens body as an IPN or asemi-IPN.

In yet another example, the wetting agent can be a linking compoundpresent in the polymerizable composition used to form the lens body, ora linking agent physically entrapped within the polymeric lens bodyafter the lens body has been formed. When the wetting agent is a linkingcompound, after polymerization of the lens body or entrapment of thelinking agent in the polymeric lens body, the linking compound cansubsequently link a second wetting agent to the lens body when the lensbody is contacted by the wetting agent. The linking can occur as part ofthe manufacturing process, for example as a washing process, or can takeplace when the lens body is contacted by a packaging solution. Thelinking can take the form of an ionic bond, or a covalent bond, or aform of van der Waals attraction. The linking agent can comprise aboronic acid moiety or group such that a polymerized boronic acid moietyor group is present in the polymeric lens body, or such that a boronicacid moiety or group is physically entrapped in the polymeric lens body.For example, when the linking agent comprises a form of boronic acid,the second wetting agent can comprise a form of poly(vinyl alcohol)which becomes bound to the form of boronic acid. Optionally, siliconehydrogel contact lenses of the present disclosure can be understood tobe free of linking agents. In one example, the silicone hydrogel contactlenses can be free of boronic acid moieties or groups, includingpolymerized boronic acid moieties or groups, that is, specifically, thesilicone hydrogel contact lenses can be formed from a polymerizablecomposition free of a form of boronic acid such as, for example, apolymerizable form of boronic acid including vinyl phenyl boronic acid(VPB), can be formed of a polymer free of units derived from apolymerizable form of boronic acid such as vinyl phenyl boronic acid(VPB), and the polymeric lens body and the silicone hydrogel contactlenses can be free of a form of boronic acid, including polymeric ornon-polymeric form of boronic acid, physically entrapped therein.Alternatively, the polymerizable composition, or the polymeric lensbody, or the silicone hydrogel contact lens, or any combination thereof,can comprise at least one linking agent.

In addition to including wetting agents in the polymerizable compositionand modifying the lens surfaces, washing polymeric lens bodies involatile organic solvents or aqueous solutions of volatile organicsolvent has been used to increase the wettability of lens surfaces.While it is possible to wash the present polymeric lens bodies in avolatile organic solvent or an aqueous solution of a volatile organicsolvent, in accordance with the present disclosure, it is not necessaryto do so in order to obtain a silicone hydrogel contact lens havingophthalmically acceptably wettable lens surfaces when fully hydrated. Inother words, in one example, the silicone hydrogel contact lenses of thepresent invention have not been exposed to a volatile organic solvent,including a solution of a volatile organic solvent, as part of amanufacturing process. In one example, the silicone hydrogel contactlenses of the present invention can be formed from a polymerizablecomposition free of a wetting agent, or the polymeric lens body and/orhydrated contact lens can be free of a wetting agent, or free of surfacetreatment, or free of a surface modification, or was not exposed to avolatile organic solvent during the manufacturing process, or anycombination thereof. Instead, for example, the silicone hydrogel contactlenses can be washed in washing liquids free of a volatile organicsolvent, such as, for example, water or an aqueous solution free of avolatile organic solvent, i.e., a liquid free of a volatile loweralcohol.

The use of volatile organic solvents to extract lens bodies contributessignificantly to production costs, due to factors such as the cost ofthe organic solvents, the cost of disposal of the solvents, the need toemploy explosion-proof production equipment, the need to remove thesolvents from the lenses prior to packaging, and the like. However,development of polymerizable compositions capable of consistentlyproducing contact lenses with ophthalmically acceptably wettable lenssurfaces when extracted in aqueous liquids free of volatile organicsolvents can be challenging. For example, it is common to findnon-wetting regions present on the lens surfaces of contact lenses whichhave been extracted in aqueous liquids free of volatile organicsolvents.

As previously discussed, in one example of the present disclosure, thecontact lenses are contact lenses which have not been exposed to avolatile organic solvent, such as a lower alcohol, during theirmanufacture. In other words, the washing, extraction and hydrationliquids used for such lenses, as well as all liquids used during wetdemolding, or wet delensing, or washing, or any other manufacturingstep, are all free of volatile organic solvents. In one example, thepolymerizable composition used to form these lenses which are notcontacted by a volatile organic solvent can comprise a hydrophilicvinyl-containing monomer or monomer component, such as, for example, ahydrophilic vinyl ether-containing monomer. The vinyl-containinghydrophilic monomer or monomer component can include, for example, VMA.The vinyl ether-containing monomers can include, for example, BVE, orEGVE, or DEGVE, or any combination thereof. In one particular example,the vinyl ether-containing monomer can be a vinyl ether-containingmonomer which is more hydrophilic than BVE, such as, for example, DEGVE.In another example, the hydrophilic monomer component of thepolymerizable composition can be a mixture of a first hydrophilicmonomer which is a vinyl-containing monomer but which is not a vinylether-containing monomer, and a second hydrophilic monomer which is avinyl ether-containing monomer. Such mixtures include, for example,mixtures of VMA and one or more vinyl ethers such as, for example, BVE,or DEGVE, or EGVE, or any combination thereof.

When present, the hydrophilic vinyl ether-containing monomer or monomercomponent can be present in the polymerizable composition in an amountfrom about 1 to about 15 unit parts, or from about 3 to about 10 unitparts. When present as a mixture with a hydrophilic vinyl-containingmonomer which is not a vinyl ether, the portion of the hydrophilicvinyl-containing monomer or monomer component which is not a vinyl etherand the hydrophilic vinyl ether-containing monomer or monomer componentcan be present in the polymerizable composition in a ratio of at least3:1, or from about 3:1 to about 15:1, or of about 4:1 based on the ratioof the unit parts by weight of the hydrophilic vinyl-containing monomeror monomer component which is not a vinyl ether to the unit parts byweight of the hydrophilic vinyl ether-containing monomer or monomercomponent.

Another approach for producing contact lenses having ophthalmicallyacceptably wettable lens surfaces in accordance with the presentdisclosure, particularly lenses extracted in a liquid free of a volatileorganic solvent and including lenses which are not contacted by avolatile organic solvent during manufacturing, can be to limit theamount of a vinyl-containing cross-linking agent or cross-linking agentcomponent included in the polymerizable composition. For example, avinyl-containing cross-linking agent or cross-linking agent componentcan be present in the polymerizable composition in an amount from about0.01 to about 0.80 unit parts, or from 0.01 to about 0.30 unit parts, orfrom about 0.05 to about 0.20 unit parts, or in an amount of about 0.1unit parts. In one example, a vinyl-containing cross-linking agent orcross-linking agent component can be present in the polymerizablecomposition in an amount effective to produce a contact lens havingimproved wettability as compared to a contact lens produced from thesame polymerizable composition but having an amount of thevinyl-containing cross-linking agent or cross-linking agent componentgreater than about 2.0 unit parts, or greater than 1.0 unit parts, orgreater than about 0.8 unit parts, or greater than about 0.5 unit parts,or greater than about 0.3 unit parts.

While limiting the amount of the vinyl-containing cross-linking agent orcross-linking agent component can improve wettability, in one example,the inclusion of a vinyl-containing cross-linking agent or cross-linkingagent component in the polymerizable composition can improve thedimensional stability of the resulting contact lens formed from thepolymerizable composition. Thus, in some polymerizable compositions, avinyl-containing cross-linking agent or cross-linking agent componentcan be present in the polymerizable in an amount effective to produce acontact lens having improved dimensional stability as compared to acontact lens produced from the same polymerizable composition butwithout the vinyl-containing cross-linking agent or cross-linking agentcomponent.

Yet another approach for producing contact lenses having ophthalmicallyacceptably wettable surfaces in accordance with the present disclosure,particularly lenses washed in a liquid free of a volatile organicsolvent, can be to include an amount of a vinyl-containing cross-linkingagent or cross-linking agent component in the polymerizable compositionbased on the ratio of the unit parts by weight of the hydrophilicvinyl-containing monomer or monomer component present in the compositionto the unit parts by weight of the vinyl-containing cross-linking agentor cross-linking agent component present in the composition. Forexample, the total unit parts of the hydrophilic vinyl-containingmonomer or monomer component and the total unit parts of thevinyl-containing cross-linking agent or cross-linking agent componentcan be present in the polymerizable composition in a ratio greater thanabout 125:1, or from about 150:1 to about 625:1, or from about 200:1 toabout 600:1, or from about 250:1 to about 500:1, or from about 450:1 toabout 500:1, based on the ratio of the unit parts by weight of all thehydrophilic vinyl-containing monomers present in the polymerizablecomposition to the total unit parts by weight of all thevinyl-containing cross-linking agents present in the polymerizablecomposition.

Certain specific examples of silicone hydrogel contact lenses will nowbe described, in accordance with the present teachings.

As one example (example A), a silicone hydrogel contact lens comprises apolymeric lens body that is the reaction product of a polymerizablecomposition comprising a first siloxane monomer represented by formula(1), wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group; a secondsiloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer having a number average molecular weight of at least 3,000daltons; and a hydrophilic amide monomer or monomer component having oneN-vinyl group; wherein the first siloxane monomer and second siloxanemonomer are present in the composition in a ratio of 2:1 based on unitparts by weight. Specifically the hydrophilic monomer can comprise orconsist of N-vinyl-N-methyl acetamide (VMA),

As a second example (example B), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A, and wherein thepolymerizable composition further comprises a hydrophobic monomer ormonomer component, specifically the hydrophobic monomer can comprise orconsist of methyl methacrylate (MMA).

As a third example (example C), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B, and whereinthe polymerizable composition further comprises a vinyl ether-containingcross-linking agent or cross-linking agent component, specifically thecross-linking agent or cross-linking agent component can comprise orconsist of triethylene glycol divinyl ether (TEGVE).

As a fourth example (example D), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C, andwherein the polymerizable composition further comprises a thermalinitiator or thermal initiator component.

As a fifth example (example E), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D, andwherein the polymerizable composition further comprises an oxygenscavenger or oxygen scavenger component.

As a sixth example (example F), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D or E,and wherein the polymerizable composition further comprises a UVabsorbing agent or UV absorbing agent component.

As a seventh example (example G), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D or Eor F, and wherein the polymerizable composition further comprises atinting agent or tinting agent component.

As an eighth example (example H), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D or Eor F or G, and wherein the second siloxane monomer is represented byformula (2), wherein R₁ of formula (2) is selected from either hydrogenatom or a methyl group; R₂ of formula (2) is selected from either ofhydrogen or a hydrocarbon group having 1 to 4 carbon atoms; m of formula(2) represents an integer of from 0 to 10; n of formula (2) representsan integer of from 4 to 100; a and b represent integers of 1 or more;a+b is equal to 20-500; b/(a+b) is equal to 0.01-0.22; and theconfiguration of siloxane units includes a random configuration. As oneexample, the second siloxane monomer can be represented by formula (2),wherein m of formula (2) is 0, n of formula (2) is one integer from 5 to10, a is one integer from 65 to 90, b is one integer from 1 to 10, R₁ offormula (2) is a methyl group, and R₂ of formula (2) is either ahydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms.

As a ninth example (example I), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D or Eor F or G or H, and wherein the polymerizable composition furthercomprises a methacrylate-containing cross-linking agent or cross-linkingagent component, specifically the cross-linking agent or agent componentcan comprise or consist of ethylene glycol dimethacrylate (EGDMA). Inthis example, when the polymerizable composition also comprises a vinylether-containing cross-linking agent as part of the cross-linking agentcomponent, specifically the cross-linking agent component can compriseor consist of triethylene glycol divinyl ether (TGDVE) in combinationwith a methacrylate-containing cross-linking agent, which canspecifically comprise or consist of ethylene glycol dimethacrylate(EGDMA). In this example, it can be appreciated that the polymerizablecomposition comprises two cross-linking agents, each having differentreactivity ratios, i.e., the polymerizable composition comprises across-linking agent component comprising or consisting of avinyl-containing cross-linking agent and a methacrylate-containingcross-linking agent, the methacrylate-containing cross-linking agenthaving polymerizable functional groups which are more reactive and whichthus react at a faster rate than the vinyl polymerizable functionalgroups present in the vinyl-containing cross-linking agent.

As a tenth example (example J), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D or Eor F or G or H or I, and wherein the polymerizable composition furthercomprises a chain transfer agent or chain transfer agent component whichcan specifically comprise or consist of allyloxy ethanol (AE).

As an eleventh example (example K), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D or Eor F or G or H or I or J, and wherein the polymerizable compositionfurther comprises a hydrophobic monomer or hydrophobic monomer componentwhich can specifically comprise or consist of ethylene glycol methylether methacrylate (EGMA).

As a twelfth example (example L), a silicone hydrogel contact lenscomprises a polymeric lens body that is the reaction product of apolymerizable composition as described in example A or B or C or D or Eor F or G or H or I or J or K, and wherein the polymerizable compositionfurther comprises a hydrophilic vinyl ether-containing monomer ormonomer component, for example, the hydrophilic vinyl ether-containingmonomer or monomer component can comprise or consist of 1,4-butanediolvinyl ether (BVE), or ethylene glycol vinyl ether (EGVE), or diethyleneglycol vinyl ether (DEGVE), or any combination thereof.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the first siloxane monomer can have anumber average molecular weight of from 400 daltons to 700 daltons.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the polymerizable composition cancomprise the at least one hydrophilic monomer. The at least onehydrophilic monomer can be present in the polymerizable composition inan amount from 30 unit parts to 60 unit parts. The at least onehydrophilic monomer can comprise at least one hydrophilicvinyl-containing monomer. The at least one hydrophilic vinyl-containingmonomer can at least one hydrophilic amide-containing monomer having oneN-vinyl group.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the polymerizable composition comprisesthe at least one cross-linking agent, and the at least one cross-linkingagent can comprise at least one vinyl-containing cross-linking agent.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the amount of the first siloxanemonomer can be from 20 to 45 unit parts of the polymerizablecomposition. The amount of the first siloxane monomer can be from 25 to40 unit parts of the polymerizable composition. The amount of the firstsiloxane monomer can be from 27 to 35 unit parts of the polymerizablecomposition.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the amount of the second siloxanemonomer can be from 1 to 20 unit parts of the polymerizable composition,as long as the ratio of 2:1 based on unit parts by weight of the firstsiloxane to the second siloxane is maintained. The amount of the secondsiloxane monomer can be from 2 to 15 unit parts of the polymerizablecomposition. The amount of the second siloxane monomer can be from 5 to13 unit parts of the polymerizable composition.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the amount of the hydrophilic monomeror monomer component present in the polymerizable composition can befrom 1 to 60 unit parts of the polymerizable composition. Thehydrophilic monomer component can constitute from 4 to 60 unit parts ofthe polymerizable composition. When the hydrophilic monomer comprises orconsists of the VMA, it can be present in an amount from 30 unit partsto 60 unit parts. VMA can be present in the polymerizable composition inan amount from about 40 unit parts to about 50 unit parts. When thehydrophilic monomers, N,N-dimethylacrylamide (DMA), 2-hydroxyethylmethacrylate (HEMA), or 2-hydroxylbutyl methacrylate (HOB), or anycombination thereof are present in the polymerizable composition as thehydrophilic monomer in the hydrophilic monomer component, each or allcan be present in amounts from about 3 to about 10 unit parts.

In any or each of the foregoing examples A-L as well as any or all otherexamples disclosed herein, the amount of the hydrophobic monomer ormonomer component present in the polymerizable composition can be from 1to 30 unit parts of the polymerizable composition. For example, thetotal amount of hydrophobic monomer or monomer component can be fromabout 5 to about 20 unit parts of the polymerizable composition. Inpolymerizable compositions in which the hydrophobic monomer MMA ispresent as the hydrophobic monomer or as part of the hydrophobic monomercomponent, the MMA can be present in an amount from about 5 to about 20unit parts, or from about 8 to about 15 unit parts.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the amount of the cross-linking agentor cross-linking agent component present in the polymerizablecomposition can be from 0.01 to 4 unit parts of the polymerizablecomposition. TEGDVE can be present in amounts from 0.01 to 1.0 unitparts. EGDMA can be present in amounts from 0.01 to 1.0 unit parts.TEGDMA can be present in amounts from 0.1 to 2.0 unit parts. Each ofthese non-silicon cross-linking agents can be present alone or in anycombination in the polymerizable composition.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, when the polymerizable compositioncontains EGMA, BVE, DEGVE, EGVE, or any combination thereof, they areeach present in amounts from 1 unit part to 20 unit parts of thepolymerizable composition. EGMA can be present in an amount from about 2unit parts to about 15 unit parts. BVE can be present in an amount from1 unit part to about 15 unit parts. BVE can be present in an amount fromabout 3 unit parts to about 7 unit parts. DEGVE can be present in anamount from 1 unit part to about 15 unit parts. DEGVE can be present inan amount from about 7 unit parts to about 10 unit parts. EGVE can bepresent in an amount from 1 unit part to about 15 unit parts, or in anamount from about 3 unit parts to about 7 unit parts.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the other optional components, such asinitiators or initiator component, tinting agents or tinting agentcomponents, UV absorbing agents or UV absorbing agent components, oxygenscavengers or oxygen scavenger components, or chain transfer agents orchain transfer agent components, can each be present in amounts fromabout 0.01 unit parts to about 3 unit parts. An initiator or initiatorcomponent can be present in the polymerizable in an amount from 0.1 unitparts to 1.0 unit parts. When a thermal initiator or thermal initiatorcomponent is present, such as Vazo-64, it can be present in an amountfrom about 0.3 to about 0.5 unit parts. Tinting agents or tinting agentcomponents can be present in amounts from 0.01 unit parts to 1 unitpart. When reactive dyes are used as tinting agents or as part of atinting agent component, such as Reactive Blue 246 or Reactive Blue 247,they can each be present in amounts of about 0.01 unit parts. UVabsorbing agents or UV absorbing agent components can be present inamounts from 0.1 unit parts to 2.0 unit parts. For example, the UVabsorbing agent UV1 described in the Examples C1 and 1-25 below can bepresent in an amount from about 0.8 to about 1.0 unit parts, such as 0.9unit parts; or the UV absorbing agent UV2 described in the Examples C1and 1-25 below, can be present in an amount from 0.5 unit parts to 2.5unit parts, such as from about 0.9 unit parts to about 2.1 unit parts.Oxygen scavengers or oxygen scavenger components can be present inamounts from 0.1 unit parts to 1.0 unit parts. As an example, whentriphenyl phosphine (TPP) or diphenyl(P-vinylphenyl)phosphine (pTPP) orany combination thereof is used as an oxygen scavenger or oxygenscavenger component in the polymerizable composition, each or thecombination can be present in an amount from 0.3 unit parts to 0.7 unitparts, such as about 0.5 unit parts. Chain transfer reagents or chaintransfer reagent components can be present in the polymerizablecomposition in an amount from 0.1 unit parts to 2.0 unit parts, and inmany of Examples C1 and 1-25 below is present in an amount from 0.2 unitparts to 1.6 unit parts. For example, the chain transfer reagentallyloxy ethanol (AE) can be present in an amount from about 0.3 toabout 1.4 unit parts.

In any or each of the foregoing examples A-L, as well as any or allother examples disclosed herein, the silicone hydrogel contact lensescan be free of a wetting agent that is present in the polymerizablecomposition, or in the polymeric lens body, or in the silicone hydrogelcontact lens. Similarly, the silicone hydrogel contact lens can havelens surfaces that are free of a surface treatment or a surfacemodification. However, in another example, the silicone hydrogel contactlens can include at least one wetting agent (i.e., a single wettingagent or two or more wetting agents present as a wetting agentcomponent) in the polymerizable composition, in the polymeric lens body,or in the silicone hydrogel contact lens. The silicone hydrogel contactlens can have treated or modified lens surfaces. In addition oralternatively, any or each of the foregoing examples A-L, as well as anyor all other examples of silicone hydrogel contact lenses disclosedherein, the contact lenses can be understood to be free of a linkingagent such as, for example, a form of boronic acid.

In another example, new polymerizable compositions are provided,including each and every polymerizable composition described herein inreference to the silicone hydrogel contact lenses and methods. Thepolymerizable compositions can be diluent-free in that they do notcontain an organic solvent, such as alcohols and the like, which canhelp reduce phase separation of the polymerizable composition. However,such diluent-free polymerizable compositions can still contain one ormore chain transfer agents, such as allyloxy ethanol. However, ifdesired, the polymerizable composition can include a diluent or adiluent component, which can be present in an amount from 1 to 20 unitparts.

As described herein, the present silicone hydrogel contact lenses whichcomprise polymeric lens bodies that comprise units derived from a firstsiloxane monomer represented by formula (1) and a second siloxanemonomer represented by formula (2) and having a number average molecularweight of at least 3,000 daltons, are dimensionally stable. The presentdisclosure also relates to a batch of silicone hydrogel contact lenses.

As used herein, a batch of silicone hydrogel contact lenses refers to agroup of two or more silicone hydrogel contact lenses, and frequently, abatch refers to at least 10, or at least 100, or at least 1,000 siliconehydrogel contact lenses. In accordance with the present disclosure, abatch of silicone hydrogel contact lenses comprises a plurality of anyof the silicone hydrogel contact lenses described herein.

When initially tested shortly after manufacturing and then tested againat a later time point, a batch of lenses can exhibit a change in itsaverage physical dimensions. As batches of lenses in accordance with thepresent disclosure are dimensionally stable, they can exhibit anacceptable level of change in their average physical dimensions. As usedherein, dimensional stability variance is understood to refer to avariance in a value of a physical dimension between a value of thephysical dimension determined when the batch of lenses is initiallytested shortly after its manufacture, and the value of the physicaldimension determined when the batch of lenses is tested again at a latertime point. The later time point can be, for example, from at least 2weeks after the initial time point, to up to 7 years after the initialtime point. The silicone hydrogel contact lenses of the batch have anaverage dimensional stability variance of less than plus or minus threepercent (±3.0%) based on averaging the lens diameter measurements of arepresentative number of lenses from the batch, such as, for example, 20lenses from the batch. For a batch of lenses, an average dimensionalstability variance of less than plus or minus three percent (±3.0%),where the average dimensional stability variance is the variance in avalue of a physical dimension when measured at an initial time pointwithin one day of a manufacturing date of the batch of lenses, and at asecond time point, where the second time point is from two weeks toseven years after the initial time point when the batch is stored atroom temperature, or, when the batch is stored at a higher temperature(i.e., under accelerated shelf life testing conditions), the second timepoint is a time point representative of storage of the batch from twoweeks to seven years at room temperature, is considered to be adimensionally stable batch. In one example, accelerated shelf lifetesting conditions which are especially useful in determining averagedimensional stability variance are for 4 weeks at 70 degrees C.,although other periods of time and other temperatures can be used. Theaverage dimensional stability variance is determined by averaging theindividual dimensional stability variances for each of therepresentative lenses using the actual diameters of representativelenses measured initially (Diameter_(Original)) and the actual diametersof representative lenses measured following (Diameter_(Final)) storageat room temperature or under accelerated shelf life conditions. Therepresentative lenses measured initially and the representative lensesmeasured following storage can be the same lenses or can be differentlenses. As used herein, the average dimensional stability variance isrepresented as a percent (%). The individual dimensional stabilityvariances are determined using the following equation (A):((Diameter_(Final)−Diameter_(Original))/Diameter_(Original))×100  (A).

On average, the diameters of the silicone hydrogel contact lenses of thebatch vary by less than three percent in either direction of a targetvalue (±3.0%). As one example, if a contact lens has a target diameter(chord diameter) of 14.20 mm, the present batch of silicone hydrogelcontact lenses will have an average diameter (average of the populationin the batch) from 13.77 mm to 14.63 mm. In one example, the dimensionalstability variance is less than plus or minus two percent (±2.0%). Asone example, if a contact lens has a target diameter (chord diameter) of14.20 mm, the present batch of silicone hydrogel contact lenses willhave an average diameter (average of the population in the batch) from13.92 mm to 14.48 mm. Preferably, the average diameter of the batch ofsilicone hydrogel contact lenses does not vary by more than plus orminus 0.20 mm from the target diameter, which is commonly from 13.00 mmto 15.00 mm.

In accelerated shelf life studies, the average dimensional stabilityvariance can be determined for contact lenses that were stored for aperiod of time at an elevated temperature, such as above 40 degrees C.,including, for example, 50 degrees C., or 55 degrees C., or 65 degreesC., or 70 degrees C., or 80 degrees C., or 95 degrees C., and the like.Or, the average dimensional stability can be determined for contactlenses that were stored for a period of time at room temperature (e.g.,about 20-25 degrees C.).

For accelerated shelf life studies, the following formula can be used todetermine the number of months of storage at a particular temperaturethat are equivalent to storage for a desired length of time at roomtemperature:Desired shelf life=[N×2^(y) ]+n  (B)

where

N=number of months of storage under accelerated conditions

2^(y)=acceleration factor

y=(test temperature−25° C.)/10° C.

n=age of lenses (in months) at start of the study

Based on this equation, the following storage times have beencalculated: 6 months of storage at 35 degrees C. is equivalent to 1 yearaging at 25 degrees C., 3 months of storage at 45 degrees C. isequivalent to 1 year of aging at 25 degrees C., 3 months of storage at55 degrees C. is equivalent to 2 years of aging at 25 degrees C., and 3months of storage at 65 degrees C. is equivalent to 4 years of aging at25 degrees C.

The present disclosure also provides methods of manufacturing siliconehydrogel contact lenses. In accordance with the present teachings, themethod comprises providing a polymerizable composition. Thepolymerizable composition, or contact lens formulation, comprises afirst siloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group. Thepolymerizable composition also comprises a second siloxane monomerrepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer having a number average molecular weight of at least 3,000daltons. The first siloxane monomer and the second siloxane monomer arepresent in the polymerizable composition in a ratio of at least 2:1based on unit parts. The polymerizable composition also comprises atleast one hydrophilic monomer, or at least one hydrophobic monomer, orat least one cross-linking agent, or any combination thereof.

The method can also comprise a step of polymerizing the polymerizablecomposition to form a polymeric lens body. The step of polymerizing thepolymerizable composition can be conducted in a contact lens moldassembly. The polymerizable composition can be cast molded between moldsformed of a thermoplastic polymer. The thermoplastic polymer used toform the molding surfaces of the mold can comprise a polar polymer, orcan comprise a non-polar polymer. Alternatively, the polymerizablecomposition can be formed into a lens via various methods known to thoseof ordinary skill in the art, such as spin casting, injection molding,forming a polymerized rod that is subsequently lathed to form a lensbody, etc.

The method can also comprise contacting the polymeric lens body with awashing liquid to remove extractable material, such as unreactedmonomers, uncross-linked materials that are otherwise not physicallyimmobilized in the polymeric lens body, diluents, and the like.

In accordance with the present disclosure, the polymeric lens body canbe packaged along with a contact lens packaging solution in a contactlens package, such as a blister pack or glass vial. Following packaging,the package can be sealed and the polymeric lens body and the contactlens packaging solution can be sterilized, for example, by autoclavingthe sealed package, to produce a silicone hydrogel contact lens product.

The present method can further comprise repeating the steps to produce aplurality of the silicone hydrogel contact lenses. The polymeric lensbodies of the plurality of silicone hydrogel contact lenses have anaverage dimensional stability variance of less than plus or minus threepercent (±3.0%) over a time period from two weeks to seven years, saidaverage dimensional stability variance being a normal average of theindividual dimensional stability variance (%) values determined from thelens diameter of each representative lens by the following equation (A):((Diameter_(Final)−Diameter_(Original))/Diameter_(Original))×100  (A).

In any of the present methods, a particular first siloxane monomer canbe provided in the polymerizable composition, such as a monomerrepresented by formula (1) wherein m of formula (1) is 4, n of formula(1) is 1, R¹ of formula (1) is a butyl group, and each R² of formula (1)is independently either a hydrogen atom or a methyl group.

In all of the present methods, the second siloxane monomer is berepresented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen or ahydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; and the configurationof siloxane units includes a random configuration. As one example, thesecond siloxane monomer can be represented by formula (2), wherein m offormula (2) is 0, n of formula (2) is one integer from 5 to 15, a is oneinteger from 65 to 90, b is one integer from 1 to 10, R₁ of formula (2)is a methyl group, and R₂ of formula (2) is either a hydrogen atom or ahydrocarbon group having 1 to 4 carbon atoms.

In the present methods, the step of contacting the polymeric lens bodywith a washing liquid can be understood to be an extraction step becauseextractable materials can be removed from the polymeric lens body duringthe process. When the washing liquid comprises water or an aqueoussolution free of a volatile organic solvent, the contacting step can beunderstood to be both an extraction step and a hydration step. Inanother example of the method, the contacting step can comprisecontacting the polymeric lens body with a washing liquid comprising avolatile organic solvent, such as a liquid containing a primary alcohol,such as methanol, ethanol, n-propyl alcohol, and the like. Some washingliquids can contain a secondary alcohol, such as isopropyl alcohol, andthe like. Using a washing liquid containing one or more volatile organicsolvents can be helpful in removing hydrophobic materials from thepolymeric lens body, and thus may increase wettability of the resultingsilicone hydrogel contact lens. Such methods may be understood to bevolatile organic solvent-based extraction steps. In other methods, thecontacting step comprises contacting the polymeric lens body with anaqueous washing liquid that is free of a volatile organic solvent. Suchmethods may be understood to be entirely aqueous washing steps, as novolatile organic solvents are included in the washing liquid.Water-based washing liquids that can be used in such methods includewater, such as deionized water, saline solutions, buffered solutions, oraqueous solutions containing surfactants or other non-volatileingredients that can improve the removal of hydrophobic components fromthe polymeric contact lens bodies, or can reduce distortion of thepolymeric contact lens bodies, compared to the use of deionized wateralone.

After washing, the contact lenses can be placed in packages, such asplastic blister packs, with a packaging solution, such as a bufferedsaline solution, which may or may not contain surfactants,anti-inflammatory agents, anti-microbial agents, contact lens wettingagents, and the like, and can be sealed and sterilized.

EXAMPLES

The following Examples C1 and 1-25 illustrate certain aspects andadvantages of the present invention, which should be understood not tobe limited thereby.

As can be readily determined by a review of the Examples below, all ofthe Example formulations are free of an organic diluent. Also, all ofthe Example formulations are free of N,N-dimethylacrylamide (DMA).Additionally, all of the Example formulations below are free of apolymeric wetting agent. Furthermore, all of the Example formulationscomprise at least one hydrophilic amide monomer having one N-vinylgroup. In many of the Example formulations, the polymerizablecomposition comprises a vinyl-containing cross-linking agent. In all ofthe Example formulations, the first siloxane monomer is a siloxanemonomer having a number average molecular weight from 400 daltons to 700daltons. A majority of the Example formulations comprise a secondsiloxane having a structure represented by formula (2);

both wherein R₁ of formula (2) is selected from either hydrogen atom ora methyl group; R₂ of formula (2) is selected from either of hydrogenatom or a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer having a number average molecular weight of at least 3,000daltons; andwherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer has a number average molecular weight of at least 3,000 daltons.

The following chemicals are referred to in Examples C1 and 1-25, and maybe referred to by their abbreviations.

Si1: 2-propenoic acid, 2-methyl-,2-[3-(9-butyl-1,1,3,3,5,5,7,7,9,9-decamethylpentasiloxane-1-yl)propoxy]ethylester (CAS number of 1052075-57-6). (Si1 was obtained from Shin-EtsuChemical Co., Ltd., Tokyo, Japan, as product number X-22-1622).

Si2: α,ω-Bis(methacryloxypropyl)-poly(dimethylsiloxane)-poly(ω-methoxy-poly(ethylenegylcol)propylmethylsiloxane) (thesynthesis of this compound can be performed as described inUS20090234089, which is incorporated herein by reference)

Si3: Poly(dimethyl siloxane), methacryloxypropyl terminated (CAS number58130-03-3; DMS-R18 available from Gelest)

VMA: N-vinyl-N-methylacetamide (CAS number 003195786)

DMA: N,N-dimethylacrylamide (CAS number 2680-03-7)

HEMA: 2-hydroxyethyl methacrylate (CAS number 868-77-9)

HOB: 2-hydroxylbutyl methacrylate (CAS number 29008-35-3)

EGMA: Ethylene glycol methyl ether methacrylate (CAS number 6976-93-8)

MMA: Methyl methacrylate (CAS number 80-62-6)

EGDMA: Ethylene glycol dimethacrylate (CAS number 97-90-5)

TEGDMA: triethylene glycol dimethacrylate (CAS number 109-16-0)

BVE: 1,4-butanediol vinyl ether (CAS number 17832-28-9)

DEGVE: diethylene glycol vinyl ether (CAS number 929-37-3)

EGVE: ethylene glycol vinyl ether (CAS number 764-48-7)

TEGDVE: triethylene glycol divinyl ether (CAS number 765-12-8)

AE: 2-Allyloxy ethanol (CAS number 111-45-5)

V-64: 2,2′-Azobis-2-methyl propanenitrile (CAS number 78-67-1)

UV1: 2-(4-benzoyl-3-hydroxyphenoxy)ethyl acrylate (CAS number16432-81-8)

UV2: 2-(3-(2H-benzotriazol-2-YL)-4-hydroxy-phenyl)ethyl methacrylate(CAS number 96478-09-0)

RBT1: 1,4-Bis[4-(2-methacryloxyethyl)phenylamino]anthroquinone (CASnumber 121888-69-5)

RBT2: 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedionebis(2-propenoic)ester (CAS Reg. No. 109561071)

TPP: Triphenyl phosphine (CAS number 603-35-0)

pTPP: polymerizable TPP: diphenyl(P-vinylphenyl)phosphine (CAS number40538-11-2)

Silicone Hydrogel Contact Lens Fabrication and Testing Procedure

The chemical compounds set forth in Examples C1 and 1-25 were, for eachexample, weighed out in amounts corresponding to the described unitparts, and combined to form a mixture. The mixture was filtered througha 0.2-5.0 micron syringe filter into a bottle. Mixtures were stored forup to about 2 weeks. The mixtures are understood to be polymerizablesilicone hydrogel contact lens precursor compositions, or as usedherein, polymerizable compositions. In Examples C1 and 1-25, the listedamounts of ingredients are given as unit parts of the polymerizablecomposition by weight.

A volume of the polymerizable composition was cast molded by placing thecomposition in contact with a lens defining surface of a female moldmember. In all of the following Examples C1 and 1-25, the moldingsurface of the female mold member was formed of a non-polar resin,specifically polypropylene. A male mold member was placed in contactwith the female mold member to form a contact lens mold assemblycomprising a contact lens shaped cavity containing the polymerizablecomposition. In the following Examples C1 and 1-25, the molding surfaceof the male mold member was formed of a non-polar resin, specificallypolypropylene.

Contact lens mold assemblies were placed in a nitrogen flushed oven toallow the polymerizable composition to thermally cure. For all ofExamples C1 and 1-25, the contact lens mold assemblies were exposed totemperatures of at least about 55° C. for about 2 hours. Examples ofcuring profiles which can be used to cure silicone hydrogel contactlenses described herein include exposing the contact lens moldassemblies to temperatures of 55° C. for 40 minutes, 80° C. for 40minutes, and 100° C. for 40 minutes. Other contact lenses can be madewith the same curing profile, but instead of the first temperature beingat 55° C., it can be at 65° C.

After polymerizing the polymerizable composition to form a polymericlens body contained within the mold assembly, the contact lens moldassemblies were demolded to separate the male and female mold members.The polymeric lens body remained adhered to the male mold or the femalemold. A dry demolding process where the mold assembly is not contactedwith a liquid medium can be used, or a wet demolding process where themold assembly is contacted with a liquid medium such as, for example,water or an aqueous solution, can be used. A mechanical dry demoldingprocess can involve applying mechanical force to a portion of one orboth of the mold members in order to separate the mold members. In allof the following Examples C1 and 1-25, a dry demolding process was used.

The polymeric lens body was then delensed from the male mold or femalemold to produce a delensed polymeric lens body. In one example of adelensing method, the polymeric lens body can be delensed from the malemold member using a dry delensing process, such as by manually peelingthe lens from the male mold member or by compressing the male moldmember and directing a gas toward the male mold member and the polymericlens body, and lifting the dry polymeric lens body with a vacuum devicefrom the male mold member, which is discarded. In other methods, thepolymeric lens body can be delensed using a wet delensing process bycontacting the dry polymeric lens body with a liquid releasing medium,such as water or an aqueous solution. For example, a male mold memberwith the attached polymeric lens body can be dipped into a receptaclecontaining a liquid until the polymeric lens body separates from themale mold member. Or, a volume of liquid releasing medium can be addedto the female mold to soak the polymeric lens body in the liquid and toseparate the lens body from the female mold member. In the followingExamples C1 and 1-25, a dry delensing process was used. Followingseparation, the lens body can be lifted from the mold member manuallyusing tweezers or using a vacuum device and placed into a tray.

The delensed lens product was then washed to remove extractablematerials from the polymeric lens body, and hydrated. Extractablematerials included polymerizable components such as, for example,monomers, or cross-linking agents, or any optional polymerizableingredients such as tints or UV blockers, or combinations thereof,present in the polymerizable composition which remain present in thepolymeric lens body in an unreacted form, in a partially reacted form,or in an uncross-linked form, or any combination thereof, followingpolymerization of the lens body and prior to extraction of the lensbody. Extractable materials may have also included any non-polymerizableingredients present in the polymerizable composition, for example, anyoptional non-polymerizable tinting agents, or UV blockers, or diluents,or chain transfer agent, or any combination thereof, remaining presentin the polymeric lens body following polymerization of the polymericlens body but prior to extraction of the polymeric lens body.

In another method, such as a method involving delensing by compressionof the male mold member and directing gas flow toward the male moldmember, the delensed polymerized contact lens bodies can be placed incavities of lens carriers or trays where the delensed polymeric lensbodies can then be contacted with one or more volumes of an extractionliquid, such as an aqueous extraction liquid free of a volatile organicsolvent, for example deionized water or an aqueous solution of asurfactant such as Tween 80, or an organic solvent-based extractionliquid such as ethanol, or an aqueous solution of a volatile organicsolvent such as ethanol.

In other methods, such as those involving wet delensing by contactingthe mold and lens with a liquid releasing medium, the delensedpolymerized contact lens bodies can be washed to remove extractablecomponents from the lens bodies using a washing liquid that is free of avolatile organic solvent, such as a lower alcohol, for example,methanol, ethanol, or any combination thereof. For example, the delensedpolymerized contact lens bodies can be washed to remove extractablecomponents from the lens bodies by contacting the lens bodies with anaqueous washing liquid free of a volatile organic solvent, such as, forexample, deionized water, or a surfactant solution, or a salinesolution, or a buffer solution, or any combination thereof. The washingcan take place in the final contact lens package, or can take place a inwashing tray or a washing tank.

In the following Examples C1 and 1-25, following the dry demolding anddry delensing steps, the dry delensed lens bodies were placed incavities of trays, and the delensed polymeric lens bodies were extractedand hydrated by contacting the polymeric lens bodies with one or morevolumes of an extraction liquid. The extraction and hydration liquidused in the extraction and hydration process consisted of either a) acombination of a volatile organic solvent-based extraction liquid and avolatile organic solvent-free hydration liquid, or b) a volatile organicsolvent-free extraction and hydration liquid, i.e., an entirelyaqueous-based extraction and hydration liquid. Specifically, in ExamplesC1 and 1-5 below, the extraction and hydration process comprised atleast two extraction steps in separate portions of ethanol, followed byat least one extraction step in a portion of a 50:50 wt/wt ethanol:watersolution of Tween 80, followed by at least three extraction andhydration steps in separate portions of a solution of Tween 80 indeionized water, wherein each extraction or extraction and hydrationstep lasted from about 5 minutes to 3 hours. In Examples 6-25 below, theextraction and hydration process used comprised at least threeextraction and hydration steps in separate portions of a solution ofTween 80 in deionized water, wherein the temperature of the Tween 80solution of the portions ranged from room temperature to about 90degrees C., and wherein each extraction and hydration step lasted fromabout 15 minutes to about 3 hours.

Washed, extracted and hydrated lenses were then placed individually incontact lens blister packages with a phosphate buffered saline packagingsolution. The blister packages were sealed and sterilized byautoclaving.

Following sterilization, lens properties such as contact angle,including dynamic and static contact angle, oxygen permeability,ionoflux, modulus, elongation, tensile strength, water content, and thelike were determined, as described herein.

For the present contact lenses, contact angles including dynamic andstatic contact angles, can be determined using routine methods known topersons of ordinary skill in the art. For example, the advancing contactangle and receding contact angle of the contact lenses provided hereincan be measured using a conventional drop shape method, such as thesessile drop method or captive bubble method.

In the following Examples C1 and 1-25, the advancing and recedingcontact angle of silicone hydrogel contact lenses was determined using aKruss DSA 100 instrument (Kruss GmbH, Hamburg), and as described in D.A. Brandreth: “Dynamic contact angles and contact angle hysteresis”,Journal of Colloid and Interface Science, vol. 62, 1977, pp. 205-212 andR. Knapikowski, M. Kudra: Kontaktwinkelmessungen nach demWilhelmy-Prinzip-Ein statistischer Ansatz zur Fehierbeurteilung”, Chem.Technik, vol. 45, 1993, pp. 179-185, and U.S. Pat. No. 6,436,481, all ofwhich are incorporated by reference herein.

As an example, the advancing contact angle and receding contact anglewas be determined using a captive bubble method using phosphate bufferedsaline (PBS; pH=7.2). The lens was flattened onto a quartz surface andrehydrated with PBS for at least 10 minutes before testing. An airbubble was placed onto a lens surface using an automated syringe system.The size of the air bubble was increased and decreased to obtain thereceding angle (the plateau obtained when increasing the bubble size)and the advancing angle (the plateau obtained when decreasing the bubblesize).

The modulus, elongation, and tensile strength values of the presentlenses can be determined using routine methods known to persons ofordinary skill in the art, such as, for example, a test method inaccordance with ANSI Z80.20. The modulus, elongation, and tensilestrength values reported herein were determined by using an InstronModel 3342 or 3343 mechanical testing system (Instron Corporation,Norwood, Mass., USA) and Bluehill Materials Testing Software, using acustom built rectangular contact lens cutting die to prepare therectangular sample strip. The modulus, elongation and tensile strengthwere determined inside a chamber having a relative humidity of least70%. The lens to be tested was soaked in phosphate buffered solution(PBS) for at least 10 minutes prior to testing. While holding the lensconcave side up, a central strip of the lens was cut using the cuttingdie. The thickness of the strip was determined using a calibrated gauge(Rehder electronic thickness gauge, Rehder Development Company, CastroValley, Calif., USA). Using tweezers, the strip was loaded into thegrips of the calibrated Instron apparatus, with the strip fitting overat least 75% of the grip surface of each grip. A test method designed todetermine the maximum load (N), the tensile strength (MPa), the strainat maximum load (% elongation) and the mean and standard deviation ofthe tensile modulus (MPa) was run, and the results were recorded.

The percent energy loss of the present silicone hydrogel contact lensescan be determined using routine methods known to persons of ordinaryskill in the art. For the following Examples C1 and 1-25, the percentenergy loss was determined using an Instron Model 3343 (InstronCorporation, Norwood, Mass., USA) mechanical testing system, with a 10Nforce transducer (Instron model no. 2519-101) and Bluehill MaterialsTesting Software including a TestProfiler module. The energy loss wasdetermined inside a chamber having a relative humidity of least 70%.Before testing, each lens was soaked in phosphate buffered solution(PBS) for at least 10 minutes. Using tweezers, the lens was loaded intothe grips of the calibrated Instron apparatus, with the lens loadedvertically between the grips as symmetrically as possible so that thelens fit over at least 75% of the grip surface of each grip. A testdesigned to determine the energy required to stretch the lens to 100%strain and then return it to 0% strain at a rate of 50 mm/minute wasthen run on the lens. The test was conducted only once on a single lens.Once the test was finished, energy loss was calculated using thefollowing equation: Lost Energy (%)=(Energy to 100% strain−Energy toreturn to 0% strain)/Energy to 100% strain×100%.

The ionoflux of the present lenses can be determined using routinemethods known to persons of ordinary skill in the art. For the lenses ofthe following Examples 1-25, the ionoflux was measured using a techniquesubstantially similar to the “Ionoflux Technique” described in U.S. Pat.No. 5,849,811, which is incorporated by reference herein. Prior tomeasurement, a hydrated lens was equilibrated in deionized water for atleast 10 minutes. The lens to be measured was placed in a lens-retainingdevice, between male and female portions. The male and female portionsincluded flexible sealing rings which were positioned between the lensand the respective male or female portion. After positioning the lens inthe lens-retaining device, the lens-retaining device was then placed ina threaded lid. The lid was screwed onto a glass tube to define a donorchamber. The donor chamber was filled with 16 ml of 0.1 molar NaClsolution. A receiving chamber was filled with 80 ml of deionized water.Leads of the conductivity meter were immersed in the deionized water ofthe receiving chamber and a stir bar was added to the receiving chamber.The receiving chamber was placed in a water bath and the temperature washeld at about 35° C. Finally, the donor chamber was immersed in thereceiving chamber such that the NaCl solution inside the donor chamberwas level with the water inside the receiving chamber. Once thetemperature inside the receiving chamber was equilibrated to 35 degreesC., measurements of conductivity were taken every 2 minutes for at least10 minutes. The conductivity versus time data was substantially linear,and was used to calculate the ionoflux value for the lenses tested.

The oxygen permeability (Dk) of the present lenses can be determinedusing routine methods known to persons of ordinary skill in the art. Forexample, the Dk value can be determined using a commercially availableinstrument under the model designation of MOCON® Ox-Tran System (MoconInc., Minneapolis, Minn., USA), for example, using the Mocon Method, asdescribed in U.S. Pat. No. 5,817,924, which is incorporated by referenceherein. The Dk values of the lenses of the following Examples 1-25 weredetermined using the method described by Chhabra et al. (2007), Asingle-lens polarographic measurement of oxygen permeability (Dk) forhypertransmissible soft contact lenses. Biomaterials 28: 4331-4342,which is incorporated by reference herein.

The equilibrium water content (EWC) of the present lenses can bedetermined using routine methods known to persons of ordinary skill inthe art. For the lenses of the following Examples C1 and 1-25 a hydratedsilicone hydrogel contact lens was removed from an aqueous liquid, wipedto remove excess surface water, and weighed. The weighed lens was thendried in an oven at 80 degrees C. under a vacuum, and the dried lens wasthen weighed. The weight difference was determined by subtracting theweight of the dry lens from the weight of the hydrated lens. The watercontent (%) is the (weight difference/hydrated weight)×100.

The percentage of the wet extractable component or dry extractablecomponent in a lens can be determined by extracting the lenses in anorganic solvent in which the polymeric lens body is not soluble inaccordance to methods known to those of ordinary skill in the art. Forthe lenses of the following Examples C1 and 1-25, an extraction inmethanol using a Sohxlet extraction process was used. For determinationof the wet extractable component, a sample (e.g., at least 5 lenses perlot) of fully hydrated and sterilized contact lenses was prepared byremoving excess packaging solution from each lens and drying themovernight in an 80° C. vacuum oven. For determination of the dryextractable component, a sample of polymeric lens bodies which had notbeen washed, extracted, hydrated or sterilized was prepared by dryingthe lens bodies overnight in an 80° C. vacuum oven. When dried andcooled, each lens was weighed to determine its initial dry weight (W1).Each lens was then placed in a perforated, stackable Teflon thimble, andthe thimbles were stacked to form an extraction column with an emptythimble placed at the top of the column. The extraction column wasplaced into a small Sohxlet extractor attached to a condenser and around bottom flask containing 70-80 ml methanol. Water was circulatedthrough the condenser and the methanol was heated until it gentlyboiled. The lenses were extracted for at least 4 hours from the timecondensed methanol first appeared. The extracted lenses were again driedovernight at 80° C. in a vacuum oven. When dried and cooled, each lenswas weighed to obtain the dry weight of the extracted lens (W2), and thefollowing calculation was made for each lens to determine the percentwet extractable component: [(W1−W2)/W1]×100.

Comparative Example C1

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure provided above.

Chemical Compound (Abbrev.) Unit parts Si1 35 VMA 42 DMA 8 MMA 15 TEGDMA0.8 V-64 0.3 UV1 0.9

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used washing liquids comprisingvolatile organic solvent-based extraction liquids and hydration liquidsconsisting of volatile organic solvent-free liquids. These contactlenses contained units derived from only a single siloxane monomer, Si1.The batch of contact lenses had unacceptable average dimensionalstability.

For example, a sample of 20 of the contact lenses were tested and foundto have an average initial chord diameter of 14.63 mm, and the averagechord diameter decreased to 14.18 mm under accelerated shelf lifetesting conditions equivalent to storage for seven years at roomtemperature. This change corresponds to an average dimensional stabilityvariance of −3.1%, reflecting that, on average, the contact lensesshrank in diameter by more than ±3.0% during the accelerated shelf lifetesting. In more detail, initially, after storage for 0 days at 95degrees C. (equivalent to 0 years at room temperature), the averagechord diameter was 14.63 mm; following storage for 6 days at 95 degreesC. (equivalent to 2 years of aging at room temperature), the averagechord diameter had decreased to 14.23 mm; following storage for 12 daysat 95 degrees C. (equivalent to 4 years of aging at room temperature),the average chord diameter had decreased to 14.20 mm; following storagefor 20 days at 95 degrees C. (equivalent to 7 years of aging at roomtemperature), the average chord diameter had decreased to 14.18 mm.

In addition, these lenses, when fully hydrated, had an EWC from 61%wt/wt to 66% wt/wt, a modulus of 0.14 MPa, an ionoflux of 11.60 (×10⁻³mm²/min), and an elongation of about 326% when tested at the start ofthe shelf life study.

Example 1

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 30 Si3 3 VMA 45 EGMA 7 MMA 15TEGDMA 0.8 AE 0.5 V-64 0.3 UV1 0.9

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used washing liquids comprisingvolatile organic solvent-based extraction liquids and hydration liquidsconsisting of volatile organic solvent-free liquids. These contactlenses contained units derived from two siloxane monomers, Si1 and Si3.This batch of contact lenses had acceptable average dimensionalstability variance.

For example, a sample of 20 of the contact lenses had an initial averagechord diameter of 13.98 mm, and the average chord diameter decreased to13.70 mm under accelerated shelf life testing conditions representativeof seven years of aging at room temperature. This change corresponds toan average dimensional stability variance of −2.0%, reflecting that thecontact lenses shrank in diameter on average by less than ±3.0% duringthe accelerated stability testing. In more detail, initially, afterstorage for 0 days at 95 degrees C. (equivalent to 0 years at roomtemperature), the average chord diameter was 13.98 mm; following storagefor 7 days at 95 degrees C. (equivalent to 2.5 years of aging at roomtemperature), the average chord diameter decreased to 13.90 mm;following storage for 14 days at 95 degrees C. (equivalent to 5 years ofaging at room temperature), the average chord diameter decreased to13.82 mm; following storage for 22 days at 95 degrees C. (equivalent to7.8 years of aging at room temperature), the average chord diameterdecreased to 13.70 mm.

Additionally, the batch of silicone hydrogel contact lenses when fullyhydrated had an average EWC from 30% wt/wt to 70% wt/wt when tested atthe start of the shelf life study.

Example 2

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 30 Si3 3 VMA 45 EGMA 7 MMA 15EGDMA 0.5 TEGDVE 0.1 AE 0.8 V-64 0.3 UV2 0.9 RBT1 0.01 TPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used washing liquids comprisingvolatile organic solvent-based extraction liquids and hydration liquidsconsisting of volatile organic solvent-free liquids. These contactlenses contained units derived from two siloxane monomers, Si1 and Si3.This batch of contact lenses had acceptable average dimensionalstability variance.

For example, the contact lenses had an average initial chord diameter of14.54±0.03 mm, and the average chord diameter decreased to 14.24±0.03 mmunder accelerated shelf life testing conditions equivalent to aging forseven years at room temperature. This change corresponds to an averagedimensional stability variance of −2.1%, reflecting that, on average,the batch of contact lens shrank in diameter by less than ±3.0%. In moredetail, after storage for 0 days at 95 degrees C. (equivalent to 0 yearsof aging at room temperature), the average chord diameter was 14.54±0.03mm; after storage for 6 days at 95 degrees C. (equivalent to 2 years ofaging at room temperature), the average chord diameter was 14.39±0.02mm; after storage for 12 days at 95 degrees C. (equivalent to 4 years ofaging at room temperature), the average chord diameter was 14.32±0.03mm; after storage for 20 days at 95 degrees C. (equivalent to 7 years ofaging at room temperature), the average chord diameter was 14.24±0.03mm.

In addition, these lenses, when fully hydrated, had an EWC of 52% wt/wt,a modulus of 0.63 MPa, and an ionoflux of 3.62 (×10⁻³ mm²/min) whentested at the start of the shelf life study.

Example 3

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 30 Si3 3 VMA 45 EGMA 7 MMA 15EGDMA 0.5 TEGDVE 0.1 AE 1.4 V-64 0.5 UV2 0.9 RBT1 0.01 TPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used washing liquids comprisingvolatile organic solvent-based extraction liquids and hydration liquidsconsisting of volatile organic solvent-free liquids. These contactlenses contained units derived from two siloxane monomers, Si1 and Si3.This batch of contact lenses had acceptable average dimensionalstability variance.

For example, a sample of 20 of the contact lenses had an average initialchord diameter of 14.03±0.03 mm, and the average chord diameterdecreased to 13.81±0.03 mm under accelerated shelf life testingconditions equivalent to seven years of aging at room temperature. Thischange corresponds to an average dimensional stability variance of−1.6%, reflecting that, on average, the contact lenses shrank indiameter by less than ±3.0%. In more detail, initially, after storagefor 0 days at 95 degrees C. (equivalent to 0 years of aging at roomtemperature), the average chord diameter was 14.03±0.03 mm; after 6 daysof storage at 95 degrees C. (equivalent to 2 years of aging at roomtemperature), the average chord diameter was 13.93±0.03 mm; after 12days of storage at 95 degrees C. (equivalent to 4 years of aging at roomtemperature), the average chord diameter was 13.87±0.03 mm; after 20days of storage at 95 degrees C. (equivalent to 7 years of aging at roomtemperature), the average chord diameter was 13.81±0.02 mm.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 52% wt/wt, a modulus of about 0.58 MPa, awet extractable content of about 0.67%, a captive bubble static contactangle of about 30 degrees; and a captive bubble dynamic advancingcontact angle of about 50.1 degrees when tested at the start of theshelf life study.

Example 4

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 30 Si2 10 VMA 45 EGMA 7 MMA15 EGDMA 0.5 TEGDVE 0.1 AE 1.4 V-64 0.5 UV2 0.9 RBT1 0.01 TPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used washing liquids comprisingvolatile organic solvent-based extraction liquids and hydration liquidsconsisting of volatile organic solvent-free liquids. These contactlenses contained units derived from two siloxane monomers, Si1 and Si2.This batch of contact lenses had acceptable average dimensionalstability variance.

For example, the contact lenses had an average initial chord diameter of14.06±0.04 mm, and the average chord diameter decreased to 13.98±0.03 mmunder accelerated shelf life testing conditions equivalent to sevenyears of aging at room temperature. This change corresponds to anaverage dimensional stability variance of −0.6%, reflecting that, onaverage, the contact lenses shrank in diameter by less than ±3.0%. Inmore detail, initially after storage for 0 days at 95 degrees C.(equivalent to 0 years of aging at room temperature), the average chorddiameter was 14.06±0.04 mm; after storage for 6 days at 95 degrees C.(equivalent to 2 years of aging at room temperature), the average chorddiameter was 13.98±0.04 mm; after 12 days of storage at 95 degrees C.(equivalent to 4 years of aging at room temperature), the average chorddiameter was 13.97±0.04 mm; after 20 days of storage at 95 degrees C.(equivalent to 7 years of aging at room temperature), the average chorddiameter was 13.98±0.03 mm.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC from 53% wt/wt to 54% wt/wt, a modulus of about0.43 MPa, a wet extractable content of about 1.23% wt/wt, a captivebubble static contact angle of about 38 degrees, a captive bubbledynamic advancing contact angle of about 50.0 degrees, an ionoflux from2.5 to 3.0 (×10⁻³ mm²/min), a Dk of 70 barrers, an elongation of about450%, a tensile strength of 1.40 MPa, a percent transmittance of 98%, anenergy loss of 36%, and a swell factor of about 21% when tested at thestart of the shelf life study. When tested prior to extraction andhydration, the polymeric lens bodies had a dry extractable content ofabout 17% wt/wt.

Example 5

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 30 Si2 10 VMA 48 EGMA 7 MMA15 EGDMA 0.5 TEGDVE 0.1 AE 1.4 V-64 0.5 UV2 0.9 RBT1 0.01 TPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used washing liquids comprisingvolatile organic solvent-based extraction liquids and hydration liquidsconsisting of volatile organic solvent-free liquids. These contactlenses contained units derived from two siloxane monomers, Si1 and Si2.This batch of contact lenses had acceptable average dimensionalstability, and had an acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses had, when fullyhydrated, an oxygen permeability greater than 60 barrers, an EWC ofabout 53% wt/wt, an ionoflux of about 2.90 (×10⁻³ mm²/min), a modulus ofabout 0.40 MPa, an elongation of about 425%, a tensile strength of about1.4 MPa, a static captive bubble contact angle of about 37 degrees, adynamic captive bubble advancing contact angle from about 48 to 52degrees, a light transmittance of about 98%, a wet extractable contentof about 1.30% wt/wt, an energy loss from about 35% to about 36%, and aswell factor of about 21% when tested at the start of the shelf lifestudy, and had an average dimensional stability variance of less thanplus or minus 3.0% after storage for at least 2 weeks at 80 degrees C.

Example 6

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 32 Si3 4 VMA 40 EGMA 5 MMA 12TEGDMA 1.0 TEGDVE 0.3 BVE 7 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si3. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses had, when fullyhydrated, an EWC of about 55% wt/wt, an ionoflux from about 3.1 (×10⁻³mm²/min), a Dk of about 72 barrers, a modulus of about 0.70 MPa, anelongation of about 345%, a tensile strength of about 2.4 MPa, a waterbreak up time greater than 20 seconds, a wet extractable component ofabout 3.9% wt/wt, and an energy loss of about 40% when tested at thestart of the shelf life study, and had an average dimensional stabilityvariance less than plus or minus 3.0% after storage for more than 2weeks at 80 degrees C. When tested prior to extraction and hydration,the polymeric lens bodies had a dry extractable component of about 11%wt/wt.

Example 7

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 32 Si3 4 VMA 50 MMA 14 TEGDMA0.8 TEGDVE 0.2 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si3. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 58% wt/wt, an ionoflux from about 4.14(×10⁻³ mm²/min), a modulus of about 0.77 MPa, an elongation of about349%, a tensile strength of about 1.75 MPa, a water break up timegreater than 20 seconds, a wet extractable content of about 4.42% wt/wt,and an energy loss of about 41% when tested at the start of the shelflife study, and had an average dimensional stability variance less thanplus or minus 3.0% after storage for at least 2 weeks at 80 degrees C.

Example 8

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 23 Si2 15 VMA 40 MMA 10 EGMA5 BVE 7 TEGDMA 1.0 TEGDVE 0.1 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 55% wt/wt, an ionoflux from about 4.19(×10⁻³ mm²/min), a modulus of about 0.61 MPa, an elongation of about275%, a tensile strength of about 1.51 MPa, a water break up timegreater than 20 seconds, and a wet extractable component of about 4.10%wt/wt when tested at the start of the shelf life study, and had anaverage dimensional stability variance less than plus or minus 3.0% formore than 2 weeks at 80 degrees C.

Example 9

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 23 Si2 15 VMA 45 MMA 10 BVE 7TEGDMA 1.0 TEGDVE 0.1 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 58% wt/wt, an ionoflux from about 2.75(×10⁻³ mm²/min), a modulus of about 0.66 MPa, an elongation of about216%, a tensile strength of about 0.87 MPa, a water break up timegreater than 20 seconds, and a wet extractable component of about 4.56%wt/wt when tested at the start of the shelf life study, and had anaverage dimensional stability variance less than plus or minus 3.0%after storage for 6 days at 95 degrees C.

Example 10

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si2 10 VMA 40 MMA 12 EGMA5 BVE 7 TEGDMA 1.2 TEGDVE 0.1 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 56% wt/wt, an ionoflux from about 3.54(×10⁻³ mm²/min), a modulus of about 0.57 MPa, an elongation of about310%, a tensile strength of about 1.90 MPa, a water break up timegreater than 20 seconds, a wet extractable component of about 4.74%wt/wt, and an energy loss from about 34 to 36% when tested at the startof the shelf life study, and had an average dimensional stabilityvariance less than plus or minus 3.0% after storage for 7 days at 80degrees C. When tested prior to extraction and hydration, the polymericlens bodies had a dry extractable component of about 14.39% wt/wt.

Example 11

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si2 10 VMA 45 MMA 12 EGMA2 BVE 5 TEGDMA 1.2 TEGDVE 0.2 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 57% wt/wt, an ionoflux from about 3.68(×10⁻³ mm²/min), a modulus of about 0.69 MPa, an elongation of about314%, a tensile strength of about 1.30 MPa, a water break up timegreater than 20 seconds, a wet extractable component of about 1.81%wt/wt, and an energy loss of about 34% when tested at the start of theshelf life study, and had an average dimensional stability variance lessthan plus or minus 3.0% after storage for 14 days at 80 degrees C.

Example 12

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si3 2 Si2 10 VMA 45 MMA 12BVE 5 TEGDMA 1.2 TEGDVE 0.2 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom three siloxane monomers, Si1, Si2 and Si3. This batch of contactlenses had acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 55% wt/wt, an ionoflux from about 3.06(×10⁻³ mm²/min), a modulus of about 0.85 MPa, an elongation of about284%, a tensile strength of about 1.88 MPa, a water break up timegreater than 20 seconds, a wet extractable component of about 2.38%wt/wt, and an energy loss of about 36% when tested at the start of theshelf life study, and had an average dimensional stability variance lessthan plus or minus 3.0% after storage for 14 days at 80 degrees C.

Example 13

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si2 10 VMA 40 MMA 12 EGMA5 BVE 7 TEGDMA 1.3 TEGDVE 0.2 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 54% wt/wt, an ionoflux from about 3.57(×10⁻³ mm²/min), a modulus of about 0.66 MPa, an elongation of about274%, a tensile strength of about 1.40 MPa, and a wet extractablecontent of about 3.8% wt/wt when tested at the start of the shelf lifestudy, and had an average dimensional stability variance less than plusor minus 3.0% after storage for 7 days at 80 degrees C.

Example 14

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si3 2 Si2 10 VMA 45 MMA 12BVE 5 TEGDMA 1.1 TEGDVE 0.2 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom three siloxane monomers, Si1, Si2 and Si3. This batch of contactlenses had acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had a modulus of about 0.81 MPa, an elongation of about 351%,a tensile strength of about 1.61 MPa, and EWC from 30% wt/wt to 70%wt/wt when tested at the start of the shelf life study, and had anaverage dimensional stability variance less than plus or minus 3.0% for14 days at 80 degrees C.

Example 15

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si3 2 Si2 10 VMA 40 EGMA15 BVE 7 TEGDMA 1.6 TEGDVE 0.2 V-64 0.5 UV2 0.9 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an ionoflux from about 3.33 (×10⁻³ mm²/min), a modulus ofabout 0.74 MPa, and an elongation of about 222% when tested at the startof the shelf life study, and had an average dimensional stabilityvariance less than plus or minus 3.0% for 14 days at 80 degrees C.

Example 16

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 32 Si3 4 VMA 45 MMA 13 EGMA 3BVE 3 TEGDMA 1.0 TEGDVE 0.2 V-64 0.5 UV2 1.3 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si3. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 57% wt/wt, a modulus of about 0.70 MPa, anenergy loss of about 40%, and a captive bubble dynamic advancing contactangle of from about 50 to about 60 degrees when tested at the start ofthe shelf life study, and had an average dimensional stability varianceless than plus or minus 3.0% for 14 days at 80 degrees C.

Example 17

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si2 10 VMA 40 MMA 12 EGMA5 BVE 7 TEGDMA 1.2 TEGDVE 0.2 V-64 0.5 UV2 1.3 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 56% wt/wt, a modulus of about 0.50 MPa,and a captive bubble dynamic advancing contact angle of from about 47 toabout 51 degrees when tested at the start of the shelf life study, andhad an average dimensional stability variance less than plus or minus3.0% for 4.4 weeks at 80 degrees C.

Example 18

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 26 Si2 10 VMA 40 MMA 12 EGMA5 BVE 3 EGDMA 0.5 TEGDVE 0.1 V-64 0.5 UV2 1.3 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 55% wt/wt, a modulus of about 0.60 MPa,and a captive bubble dynamic advancing contact angle of from about 47 toabout 55 degrees when tested at the start of the shelf life study, andhad an average dimensional stability variance less than plus or minus3.0% after storage for 2 weeks at 80 degrees C.

Example 19

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 29 Si2 8 VMA 42 MMA 14 DEGVE7 EGDMA 0.6 TEGDVE 0.08 V-64 0.5 UV2 1.3 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC from about 55% wt/wt to about 56% wt/wt, a modulusof about 0.71 MPa, and a captive bubble dynamic advancing contact angleof from about 45 to about 47 degrees when tested at the start of theshelf life study, and had an average dimensional stability variance lessthan plus or minus 3.0% for at least 2 weeks at 80 degrees C.

Example 20

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 29 Si2 8 VMA 44 MMA 14 EGVE 5EGDMA 0.6 TEGDVE 0.15 V-64 0.5 UV2 1.3 RBT2 0.01

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 56% wt/wt, and a modulus of about 0.65 MPawhen tested at the start of the shelf life study, and had an averagedimensional stability variance less than plus or minus 3.0% for 2 weeksat 80 degrees C.

Example 21

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 29 Si2 8 VMA 45 MMA 13 HEMA 4EGDMA 0.5 TEGDVE 0.1 V-64 0.5 UV2 1.7 RBT2 0.01 pTPP 0.5 AE 0.3

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of from about 55% wt/wt to about 56% wt/wt, amodulus of about 0.53 MPa, a captive bubble dynamic advancing contactangle of from about 51 to about 53 degrees, and an energy loss of about34% when tested at the start of the shelf life study, and had an averagedimensional stability variance less than plus or minus 3.0% for 4.4weeks at 80 degrees C.

Example 22

A polymerizable silicone composition was obtained by mixing andfiltering the following chemical compounds in the specified amounts,using the procedure described in the Silicone Hydrogel Contact LensFabrication and Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 29 Si2 8 VMA 42 MMA 8 EGMA 6DEGVE 7 EGDMA 0.6 TEGDVE 0.1 V-64 0.5 UV2 1.7 RBT2 0.01 pTPP 0.5 AE 0.4

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC from 57% wt/wt to 58% wt/wt, an ionoflux of about2.9 (×10⁻³ mm²/min), a modulus of about 0.7 MPa, an elongation of about300%, a tensile strength of about 1.5 MPa, a captive bubble dynamicadvancing contact angle of from about 44 to about 48 degrees, a wetextractable component of about 5.10% wt/wt, and an energy loss fromabout 32% to about 33% when tested at the start of the shelf life study,and had an average dimensional stability variance less than plus orminus 3.0% after storage for 4.4 weeks at 80 degrees C. When testedprior to extraction and hydration, the polymeric lens bodies had a dryextractable component of about 12.2% wt/wt.

Example 23

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 29 Si2 8 VMA 45 HOB 7 EGMA 10EGDMA 0.5 TEGDVE 0.1 V-64 0.5 UV2 1.7 RBT2 0.01 pTPP 0.5 AE 0.3

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC from about 55% wt/wt to about 56% wt/wt, anionoflux of about 4.1 (×10⁻³ mm²/min), a modulus of about 0.6 MPa, anelongation of about 275%, a tensile strength of about 1.2 MPa, a captivebubble dynamic advancing contact angle of from about 55 to about 58degrees, a wet extractable component of about 4.6% wt/wt, an energy lossfrom about 31% to about 32%, and a swell factor of about 27% when testedat the start of the shelf life study, and had an average dimensionalstability variance less than plus or minus 3.0% for after storage for4.4 weeks at 80 degrees C. When tested prior to extraction andhydration, the polymeric lens bodies had a dry extractable component ofabout 10.6% wt/wt.

Example 24

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 30 Si2 7 VMA 44 MMA 8 EGMA 6BVE 4 DEGVE 10 EGDMA 0.6 TEGDVE 0.1 V-64 0.5 UV2 1.8 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Sit. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC of about 61% wt/wt, an ionoflux of about 3.8 (×10⁻³mm²/min), a modulus of about 0.5 MPa, an elongation of about 279%, atensile strength of about 1.2 MPa, a captive bubble dynamic advancingcontact angle of from about 45 to about 47 degrees, a wet extractablecomponent of about 4.55% wt/wt, and an energy loss from about 30% toabout 33% when tested at the start of the shelf life study, and had anaverage dimensional stability variance less than plus or minus 3.0%after storage for 14 days at 80 degrees C. When tested prior toextraction and hydration, the polymeric lens bodies had a dryextractable component of about 13.65% wt/wt.

Example 25

A polymerizable composition was obtained by mixing and filtering thefollowing chemical compounds in the specified amounts, using theprocedure described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure given above.

Chemical Compound (Abbrev.) Unit parts Si1 30 Si2 7 VMA 45 MMA 12 EGMA 5BVE 5 TEGDMA 1.4 TEGDVE 0.2 V-64 0.5 UV2 1.8 RBT2 0.01 pTPP 0.5

A batch of silicone hydrogel contact lenses was prepared using thisformulation and tested in accordance with the fabrication procedure andtest methods described in the Silicone Hydrogel Contact Lens Fabricationand Testing Procedure, using a dry demolding process, a dry delensingprocess, and a washing process which used extraction and hydrationliquids consisting of volatile organic solvent-free extraction liquids.The lenses of this batch were not exposed to a volatile organic solventduring their manufacture. These contact lenses contained units derivedfrom two siloxane monomers, Si1 and Si2. This batch of contact lenseshad acceptable average dimensional stability variance.

In addition, these silicone hydrogel contact lenses, when fullyhydrated, had an EWC from about 55% wt/wt to about 57% wt/wt, anionoflux of about 3.6 (×10⁻³ mm²/min), a modulus of about 0.7 MPa, anelongation of about 285%, a tensile strength of about 1.3 MPa, a captivebubble dynamic advancing contact angle of from about 47 to about 53degrees, a wet extractable component of about 4.10% wt/wt, and an energyloss from about 34% to about 35% when tested at the start of the shelflife study, and had an average dimensional stability variance less thanplus or minus 3.0% after storage for 14 days at 80 degrees C. Whentested prior to extraction and hydration, the polymeric lens bodies werefound to have a dry extractable component of about 9.80% wt/wt.

Although the disclosure herein refers to certain illustratedembodiments, it is to be understood that these embodiments are presentedby way of example and not by way of limitation. The intent of theforegoing detailed description, although discussing exemplaryembodiments, is to be construed to cover all modifications,alternatives, and equivalents of the embodiments as may fall within thespirit and scope of the invention as defined by the additionaldisclosure.

A number of publications and patents have been cited hereinabove. Eachof the cited publications and patents are hereby incorporated byreference in their entireties.

What is claimed is:
 1. A silicone hydrogel contact lens, comprising: apolymeric lens body that is the reaction product of a polymerizablecomposition, said polymerizable composition comprising (a) a firstsiloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group; (b) a secondsiloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer having a number average molecular weight of at least 3,000daltons; and (c) at least one hydrophilic monomer, or at least onehydrophobic monomer, or at least one cross-linking agent, or anycombination thereof, wherein the first siloxane monomer and the secondsiloxane monomer are present in the polymerizable composition in a ratioof at least 2:1 based on unit parts.
 2. The contact lens of claim 1which has an oxygen permeability of at least 55 barrers, or anequilibrium water content from about 30% wt/wt to about 70% wt/wt, or atensile modulus from about 0.2 MPa to about 0.9 MPa, or any combinationthereof.
 3. The contact lens of claim 1, wherein in the first siloxanemonomer, m of formula (1) is 4, n is 1, R¹ of formula (1) is a butylgroup, and each R² of formula (1) is independently either a hydrogenatom or a methyl group.
 4. The contact lens of claim 1, wherein thefirst siloxane monomer has a number average molecular weight of from 400daltons to 700 daltons.
 5. The contact lens of claim 1, wherein thesecond siloxane monomer has a number average molecular weight greaterthan 7,000 daltons.
 6. The contact lens of claim 1, wherein in thesecond siloxane monomer, m of formula (2) is 0, n of formula (2) is oneinteger from 5 to 10, a is one integer from 65 to 90, b is one integerfrom 1 to 10, and R₁ of formula (2) is a methyl group.
 7. The contactlens of claim 1, wherein the polymerizable composition comprises the atleast one hydrophilic monomer, and the at least one hydrophilic monomercomprises at least one hydrophilic vinyl-containing monomer.
 8. Thecontact lens of claim 7, wherein the at least one vinyl-containingmonomer comprises at least one hydrophilic amide-containing monomerhaving one N-vinyl group.
 9. The contact lens of claim 1, wherein thepolymerizable composition comprises the at least one hydrophilicmonomer, and the at least one hydrophilic monomer is present in thepolymerizable composition in an amount from 30 unit parts to 60 unitparts.
 10. The contact lens of claim 1, wherein the polymerizablecomposition comprises the at least one cross-linking agent, and the atleast one cross-linking agent comprises at least one vinyl-containingcross-linking agent.
 11. A batch of silicone hydrogel contact lenses,comprising a plurality of the contact lens recited in claim 1, whereinthe batch of silicone hydrogel contact lenses have an averagedimensional stability variance of less than plus or minus three percent(±3.0%), where the average dimensional stability variance is thevariance in a value of a physical dimension when measured at an initialtime point within one day of a manufacturing date of the batch oflenses, and at a second time point, where the second time point is fromtwo weeks to seven years after the initial time point when the batch isstored at room temperature, or, when the batch is stored at a highertemperature, the second time point is a time point representative ofstorage of the batch from two weeks to seven years at room temperature,said average dimensional stability variance being an average of thedimensional stability variance determined for at least 20 individuallenses of the batch by the following equation (A):(Diameter_(Final)−Diameter_(Original)/Diameter_(Original))×100  (A). 12.The batch of silicone hydrogel contact lenses recited in claim 11,wherein the average dimensional stability variance is less than plus orminus two percent (±2.0%).
 13. A method of manufacturing a siliconehydrogel contact lens, comprising: providing a polymerizablecomposition, said polymerizable composition comprising (a) a firstsiloxane monomer represented by formula (1):

wherein m of formula (1) represents one integer from 3 to 10, n offormula (1) represents one integer from 1 to 10, R¹ of formula (1) is analkyl group having from 1 to 4 carbon atoms, and each R² of formula (1)is independently either a hydrogen atom or a methyl group; (b) a secondsiloxane monomer represented by formula (2):

wherein R₁ of formula (2) is selected from either hydrogen atom or amethyl group; R₂ of formula (2) is selected from either of hydrogen atomor a hydrocarbon group having 1 to 4 carbon atoms; m of formula (2)represents an integer of from 0 to 10; n of formula (2) represents aninteger of from 4 to 100; a and b represent integers of 1 or more; a+bis equal to 20-500; b/(a+b) is equal to 0.01-0.22; the configuration ofsiloxane units includes a random configuration; and the second siloxanemonomer having a number average molecular weight of at least 3,000daltons; and (c) at least one hydrophilic monomer, or at least onehydrophobic monomer, or at least one cross-linking agent, or anycombination thereof, wherein the first siloxane monomer and the secondsiloxane monomer are present in the polymerizable composition in a ratioof at least 2:1 based on unit parts by weight; polymerizing thepolymerizable composition in a contact lens mold assembly to form apolymeric lens body; contacting the polymeric lens body with a washingliquid to remove extractable material from the polymeric lens body; andpackaging the polymeric lens body in a contact lens packaging solutionin a contact lens package.
 14. The method of claim 13, furthercomprising repeating the steps to produce a plurality of the siliconehydrogel contact lenses having an average dimensional stability varianceof less than plus or minus three percent (±3.0%) over a time period fromtwo weeks to seven years when stored at room temperature, or, whenstored under accelerated shelf life testing conditions, for a timeperiod and temperature equivalent to storage from two weeks to sevenyears at room temperature, said average dimensional stability variancebeing an average of the dimensional stability variance determined for atleast 20 individual lenses of the batch by the following equation (A):((Diameter_(Final)−Diameter_(Original))/Diameter_(Original))×100  (A).15. The method of claim 13, wherein in the first siloxane monomer, m offormula (1) is 4, n of formula (1) is 1, R¹ is a butyl group, and eachR² of formula 1) is independently either a hydrogen atom or a methylgroup.
 16. The method of claim 13, wherein the first siloxane monomerhas a number average molecular weight from about 400 daltons to about700 daltons.
 17. The method of claim 13, wherein the second siloxanemonomer has a number average molecular weight greater than 7,000daltons.
 18. The method of claim 13, wherein in the second siloxanemonomer, m of formula (2) is 0, n of formula (2) is one integer from 5to 10, a is one integer from 65 to 90, b is one integer from 1 to 10,and R₁ of formula (2) is a methyl group.
 19. The method of claim 13,wherein the contacting step comprises contacting the polymeric lens bodywith a washing liquid comprising a volatile organic solvent.
 20. Themethod of claim 13, wherein the contacting step comprises contacting thepolymeric lens body with an aqueous washing liquid that is free of avolatile organic solvent.